________________________________________________________________________________
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                            ------------------------
 
                                AMENDMENT NO. 20
                                       TO
                                 SCHEDULE 14D-1
              TENDER OFFER STATEMENT PURSUANT TO SECTION 14(d)(1)
                                     OF THE
                        SECURITIES EXCHANGE ACT OF 1934
                            ------------------------
 
                                AMP INCORPORATED
                           (NAME OF SUBJECT COMPANY)
 
                          PMA ACQUISITION CORPORATION
                          A WHOLLY OWNED SUBSIDIARY OF
                               ALLIEDSIGNAL INC.
                                    (BIDDER)
 
                        COMMON STOCK, WITHOUT PAR VALUE
            (INCLUDING THE ASSOCIATED COMMON STOCK PURCHASE RIGHTS)
                         (TITLE OF CLASS OF SECURITIES)
 
                                   031897101
                     (CUSIP NUMBER OF CLASS OF SECURITIES)
 
                            PETER M. KREINDLER, ESQ.
                               ALLIEDSIGNAL INC.
                               101 COLUMBIA ROAD
                          MORRISTOWN, NEW JERSEY 07692
                                 (973) 455-5513
          (NAME, ADDRESS AND TELEPHONE NUMBER OF PERSON AUTHORIZED TO
            RECEIVE NOTICES AND COMMUNICATIONS ON BEHALF OF BIDDERS)
                            ------------------------
 
                                   COPIES TO:
                             ARTHUR FLEISCHER, ESQ.
                    FRIED, FRANK, HARRIS, SHRIVER & JACOBSON
                               ONE NEW YORK PLAZA
                         NEW YORK, NEW YORK 10004-1980
                                 (212) 859-8120
                            ------------------------
 
                           CALCULATION OF FILING FEE

- ------------------------------------------------------------------------------------------------------------------
- ------------------------------------------------------------------------------------------------------------------
                                                       
                 TRANSACTION VALUATION*                                    AMOUNT OF FILING FEE**
- ------------------------------------------------------------------------------------------------------------------
                      $890,000,000                                                $178,000
- ------------------------------------------------------------------------------------------------------------------
- ------------------------------------------------------------------------------------------------------------------

 * Based on the offer to purchase 20,000,000 shares of Common Stock of AMP
   Incorporated together with the associated Common Stock Purchase Rights at
   $44.50 cash per share.
 
** The amount of the filing fee calculated in accordance with Rule 0-11(d) of
   the Securities Exchange Act of 1934, as amended, equals 1/50th of one percent
   of the aggregate value of cash offered by PMA Acquisition Corporation for
   such number of Shares. The amount of $1,997,590 was paid upon previous
   filings of this Schedule 14D-1. Accordingly, no additional fee is paid at
   this time and $1,819,590 should be credited to the account of the Bidder.
                            ------------------------
 
[x] Check box if any part of the fee is offset as provided by Rule 0-11(a)(2)
    and identify the filing with which the offsetting fee was previously paid.
    Identify the previous filing by registration on statement number of the form
    or schedule and the date of its filing.

                                                     
AMOUNT PREVIOUSLY PAID:    $1,997,590         FILING PARTY:   AMP Acquisition Corporation and
                                                              AlliedSignal Inc.
FORM OF REGISTRATION NO.:  Schedule 14D-1     DATE FILED:     August 10, 1998

________________________________________________________________________________

     This Amendment No. 20 amends the Tender Offer Statement on Schedule 14D-1
filed on August 10, 1998 as amended (the 'Schedule 14D-1'), by AlliedSignal Inc.
('Parent'), and its wholly owned subsidiary, PMA Acquisition Corporation, a
Delaware corporation ('Offeror'), relating to Purchaser's offer to purchase up
to an aggregate of 20,000,000 shares of Common Stock of AMP Incorporated
together with the associated Common Stock Purchase Rights at $44.50 cash per
share upon the terms and subject to the conditions set forth in the Offer to
Purchase, dated August 10, 1998 (the 'Offer to Purchase'), as amended and
supplemented by the First Supplement to the Offer to Purchase, dated September
14, 1998 (the 'First Supplement') and by the Second Supplement to the Offer to
Purchase, dated September 21, 1998 (the 'Second Supplement'), and in the
revised Letter of Transmittal (which, together with any amendments or
supplements thereto, constitute the 'Offer'). Unless otherwise defined herein,
all capitalized terms used herein shall have the respective meanings given
such terms in the Offer to Purchase, the First Supplement, the Second
Supplement or the Schedule 14D-1.
 
ITEM 1. SECURITY AND SUBJECT COMPANY.
 
     Item 1 is hereby amended and supplemented by the following:
 
          (c) The information set forth in Section 3 ('Price Range of Common
     Stock; Dividends') of the Second Supplement is incorporated herein by
     reference.
 
ITEM 4. SOURCE AND AMOUNT OF FUNDS OR OTHER CONSIDERATION.
 
     Item 4 is hereby amended and supplemented by the following:
 
          (a) The information set forth in Section 4 ('Source and Amount of
     Funds') of the Second Supplement is incorporated herein by reference.
 
ITEM 5. PURPOSE OF THE TENDER OFFER AND PLANS OR PROPOSALS OF THE BIDDER.
 
     Item 5 is hereby amended and supplemented by the following:
 
          (a) The information set forth in Section 5 ('Background of the Offer;
     Contacts with the Company') of the Second Supplement is incorporated herein
     by reference.
 
ITEM 10. ADDITIONAL INFORMATION.
 
     Item 10 is hereby amended and supplemented by the following:
 
          (b), (c) and (e) The information set forth in Section 8 ('Certain
     Legal Matters, Regulatory Approvals; Certain Litigation') of the Second
     Supplement is incorporated herein by reference.
 
          (f) The information set forth in the Second Supplement and the revised
     Letter of Transmittal, copies of which are attached hereto as Exhibits (a)
     (44) and (a) (45), respectively, is incorporated herein by reference in its
     entirety.
 
ITEM 11. MATERIAL TO BE FILED AS EXHIBITS.
 
     Item 11 is supplemented by the following:
 
          (a)(44) Second Supplement to the Offer to Purchase, dated September
     21, 1998.
 
          (a)(45) Revised Letter of Transmittal.
 
          (a)(46) Revised Letter to Brokers, Dealers, Commercial Banks, Trust
     Companies and Other Nominees.
          
          (a)(47) Guidelines for Certification of Taxpayer Identification Number
     on Substitute Form W-9.

          (a)(48) Revised Letter to Clients for use by Brokers, Dealers,
     Commercial Banks, Trust Companies and Other Nominees.
 
          (a)(49) Newspaper Advertisement, dated September 21, 1998.
 
                                       2

                                   SIGNATURE
 
     After due inquiry and to the best of its knowledge and belief, each of the
undersigned certifies that the information set forth in this statement is true,
complete and correct.
 
Dated: September 21, 1998
 
                                          PMA ACQUISITION CORPORATION
 
                                          By:       /S/ PETER M. KREINDLER
                                             ...................................
                                             NAME:   PETER M. KREINDLER
                                             TITLE:  VICE PRESIDENT,
                                                     SECRETARY AND DIRECTOR
 
                                          ALLIEDSIGNAL INC.
 
                                          By:       /S/ PETER M. KREINDLER
                                             ...................................
                                             NAME:   PETER M. KREINDLER
                                             TITLE:  SENIOR VICE PRESIDENT,
                                                   GENERAL COUNSEL AND SECRETARY
 
                                       3

                                 EXHIBIT INDEX

EXHIBIT                                               DESCRIPTION                                           PAGE NO.
- -------------  ------------------------------------------------------------------------------------------   --------

(a)(44) --     Second Supplement to the Offer to Purchase, dated September 21, 1998......................
(a)(45) --     Revised Letter of Transmittal.............................................................
(a)(46) --     Revised Letter to Brokers, Dealers, Commercial Banks, Trust Companies and Other
               Nominees..................................................................................
(a)(47) --     Guidelines for Certification of Taxpayer Identification Number on
               Substitute Form W-9........................................................................
(a)(48) --     Revised Letter to Clients for use by Brokers, Dealers, Commercial Banks, Trust Companies
               and Other Nominees........................................................................
(a)(49) --     Newspaper Advertisement, dated September 21, 1998.........................................

                                       4

   SECOND SUPPLEMENT TO THE OFFER TO PURCHASE FOR CASH, DATED AUGUST 10, 1998
                          PMA ACQUISITION CORPORATION
                          A WHOLLY OWNED SUBSIDIARY OF
                               ALLIEDSIGNAL INC.
                                HAS AMENDED ITS
                           OFFER TO PURCHASE FOR CASH
             AND IS NOW OFFERING TO PURCHASE UP TO AN AGGREGATE OF
                       20,000,000 SHARES OF COMMON STOCK
            (INCLUDING THE ASSOCIATED COMMON STOCK PURCHASE RIGHTS)
                                       OF
                                AMP INCORPORATED
                                       AT
                      $44.50 NET PER SHARE OF COMMON STOCK
 
- ------------------------------------------------------------------------------ 
     THE OFFER AND WITHDRAWAL RIGHTS HAVE BEEN EXTENDED. THE OFFER, WITHDRAWAL
RIGHTS AND THE PRORATION PERIOD WILL EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY
TIME, ON FRIDAY, OCTOBER 2, 1998, UNLESS THE OFFER IS EXTENDED.
- ------------------------------------------------------------------------------ 
 
                                   IMPORTANT
 
     BECAUSE THE OFFER, AS AMENDED, CONTEMPLATES THE PURCHASE OF UP TO AN
AGGREGATE OF 20,000,000 SHARES (APPROXIMATELY 9.1% OF THE NUMBER OF OUTSTANDING
SHARES AS REPORTED IN THE COMPANY 1998 SECOND QUARTER 10-Q), OFFEROR BELIEVES
THAT THE AMENDED BUSINESS COMBINATION CONDITION, THE AMENDED CONTROL SHARE
CONDITION AND THE AMENDED RIGHTS CONDITION (EACH AS DEFINED IN THE FIRST
SUPPLEMENT) WILL BE SATISFIED FOR PURPOSES OF THE OFFER. THE OFFER, AS AMENDED,
IS NO LONGER SUBJECT TO THE HSR CONDITION OR THE MINIMUM CONDITION (EACH AS
DEFINED IN THE OFFER TO PURCHASE). SEE SECTION 8 OF THE FIRST SUPPLEMENT AND
SECTION 7 OF THIS SECOND SUPPLEMENT.
                            ------------------------
                                   IMPORTANT
 
     Any shareholder desiring to tender Shares (and, if applicable, Rights)
should either (1) complete and sign the revised Letter of Transmittal delivered
herewith or one of the Letters of Transmittal previously delivered by Parent and
Offeror (or a facsimile thereof) in accordance with the instructions in the
Letters of Transmittal, including any required signature guarantees, and mail or
deliver one of the Letters of Transmittal (or a facsimile thereof) with the
certificates for the tendered Shares and all other required documents to the
Depositary or tender Shares pursuant to the procedures for book-entry transfer
set forth in Section 3 of the Offer to Purchase (as defined herein), or (2)
request the shareholder's broker, dealer, commercial bank, trust company or
other nominee to effect the transaction for the shareholder. Shareholders having
Shares registered in the name of a broker, dealer, commercial bank, trust
company or other nominee must contact the broker, dealer, commercial bank, trust
company or other nominee if they desire to tender Shares so registered.
Shareholders will be required to tender one Right for each Share tendered in
order to effect a valid tender of a Share.
 
     TO BE VALID, A TENDER OF SHARES MUST BE ACCOMPANIED BY CERTIFICATES
REPRESENTING SHARES OR THE BOOK-ENTRY TRANSFER PROCEDURES MUST BE COMPLIED WITH
ON A TIMELY BASIS. SHARES MAY NOT BE TENDERED PURSUANT TO GUARANTEED DELIVERY
PROCEDURES AFTER SEPTEMBER 14, 1998.
 
     SHAREHOLDERS WHO HAVE PREVIOUSLY VALIDLY TENDERED SHARES PURSUANT TO THE
OFFER AND WHO HAVE NOT WITHDRAWN THOSE SHARES NEED NOT TAKE ANY FURTHER ACTION
IN ORDER TO TENDER SHARES PURSUANT TO THE OFFER, AS AMENDED. SHAREHOLDERS WHO
HAVE TENDERED SHARES ON OR PRIOR TO SEPTEMBER 11, 1998 PURSUANT TO GUARANTEED
DELIVERY PROCEDURES SHOULD COMPLY WITH THE REQUIRED PROCEDURES. SEE SECTION 3 OF
THE OFFER TO PURCHASE.
 
     Questions and requests for assistance may be directed to the Information
Agent or the Dealer Managers at their respective addresses and telephone numbers
set forth on the back cover of this Second Supplement. Additional copies of the
Offer to Purchase, the First Supplement, the Letters of Transmittal and other
related materials may also be obtained from the Information Agent or from
brokers, dealers, commercial banks or trust companies.
                            ------------------------
                     The Dealer Managers for the Offer are:
 
LAZARD FRERES & CO. LLC                                     GOLDMAN, SACHS & CO.
- ------------
 
SEPTEMBER 21, 1998

                      [THIS PAGE INTENTIONALLY LEFT BLANK]

                               TABLE OF CONTENTS

                                                                                                              PAGE
                                                                                                              ----
                                                                                                           
INTRODUCTION...............................................................................................     1
   1. Terms of the Offer; Proration; Expiration Date.......................................................     3
   2. Procedures for Tendering Shares......................................................................     3
   3. Price Range of Common Stock; Dividends...............................................................     4
   4. Source and Amount of Funds...........................................................................     4
   5. Background of the Offer; Contacts with the Company...................................................     5
   6. Purposes of the Offer and the Proposed Merger; Plans for the Company; Certain Considerations.........     5
   7. Conditions of the Offer..............................................................................     5
   8. Certain Legal Matters; Regulatory Approvals; Certain Litigation......................................     6
   Annex 1.................................................................................................   A-1

                                       i

                      [THIS PAGE INTENTIONALLY LEFT BLANK]

To: All Holders of Common Stock of AMP Incorporated.
 
                                  INTRODUCTION
 
     The following information amends and supplements the Offer to Purchase,
dated August 10, 1998 (the 'Offer to Purchase'), as amended by the First
Supplement, dated September 14, 1998 (the 'First Supplement'), of PMA
Acquisition Corporation ('Offeror'), a Delaware corporation and a wholly owned
subsidiary of AlliedSignal Inc., a Delaware corporation ('Parent'), pursuant to
which Offeror is offering to purchase shares of common stock, without par value
(the 'Shares'), of AMP Incorporated, a Pennsylvania corporation (the 'Company'),
including the associated Common Stock Purchase Rights (the 'Rights'), issued
pursuant to the Rights Agreement, dated as of October 25, 1989, as amended,
between the Company and ChaseMellon Shareholder Services L.L.C., as Rights Agent
(the 'Rights Agreement'). Unless the context otherwise requires, all references
to Shares include the associated Rights, and all references to the Rights
include the benefits that may inure to holders of the Rights pursuant to the
Rights Agreement, including the right to receive any payment due upon redemption
of the Rights.
 
     On September 14, 1998 Parent and Offeror amended the Offer to Purchase to
reduce the number of Shares to be purchased to 40,000,000, approximately the
maximum number of Shares (based on the number of Shares outstanding as reported
in the Company 1998 Second Quarter 10-Q) that Offeror could acquire without
becoming an 'Acquiring Person' under the Rights Agreement.
 
     At a meeting held on September 17, 1998, the Company Board approved
Amendment No. 4 to the Rights Agreement which amends the definition of the term
'Acquiring Person' to reduce from 20% to 10% the Share ownership threshold at
which a person who has made an unsolicited acquisition proposal may become an
Acquiring Person and thereby trigger a number of the provisions of the Rights
Agreement. Amendment No. 4 also contains a provision (the 'Shareholder Rights
Proposal Nullification Provision') that provides that the Rights Agreement will
not be amendable, the Rights will not be redeemable and the Company Board will
not be entitled to exercise certain discretionary authority otherwise available
or take certain other actions, upon the adoption of a By-law intended to limit
the authority of the Company Board and/or confer authority on any person other
than the Company Board to take action with respect to the Rights Agreement and
the Rights issued thereunder. Parent's Shareholder Rights Proposal, if approved
by the Company's shareholders, would adopt such a By-law. Amendment No. 4 does
not become effective until September 24, 1998. Once effective, Amendment No. 4
applies to all actions which have occurred on or after September 17, 1998 (the
date of the amendment).
 
     Parent and Offeror believe that the Shareholder Rights Proposal
Nullification Provision is illegal and unenforceable and is seeking judicial
declaratory relief to this effect. See Section 8 of this Second Supplement.
 
     In order to avoid triggering the Rights under the Rights Agreement, as
amended by the September 17 amendment, Offeror is now offering to purchase up to
an aggregate of 20,000,000 Shares at $44.50 per Share, net to the seller in
cash, without interest (the 'Offer Price'), upon the terms and subject to the
conditions set forth in the Offer to Purchase, as amended by the First
Supplement and this Second Supplement, and in the revised Letter of Transmittal
(which, as amended from time to time, collectively constitute the 'Offer').
 
     BECAUSE THE OFFER, AS AMENDED, CONTEMPLATES THE PURCHASE OF UP TO AN
AGGREGATE OF 20,000,000 SHARES (APPROXIMATELY 9.1% OF THE NUMBER OF OUTSTANDING
SHARES AS REPORTED IN THE COMPANY 1998 SECOND QUARTER 10-Q), OFFEROR BELIEVES
THAT THE AMENDED BUSINESS COMBINATION CONDITION, THE AMENDED CONTROL SHARE
CONDITION AND THE AMENDED RIGHTS CONDITION WILL BE SATISFIED FOR PURPOSES OF THE
OFFER. THE OFFER, AS AMENDED, IS NO LONGER SUBJECT TO THE HSR CONDITION OR THE
MINIMUM CONDITION. SEE SECTION 8 OF THE FIRST SUPPLEMENT AND SECTION 7 OF THIS
SECOND SUPPLEMENT.
 
                                       1

     If Offeror becomes aware that the purchase of 20,000,000 Shares would
constitute the purchase of 10% or more of the outstanding Shares or if any other
event occurs that would result in Offeror being the beneficial owner of 10% or
more of the outstanding Shares, Offeror intends to take that action (if any) it
deems appropriate or advisable, including selling Shares (whether 'short' or
otherwise) in the market or tendering into any competing tender offer, so that
Offeror will not be an 'Acquiring Person' under the Rights Agreement. Similarly,
if Offeror becomes aware that the purchase of 20,000,000 Shares would constitute
the purchase of 20% or more of the outstanding Shares or if any other event
occurs that would result in Offeror being the beneficial owner of 20% or more of
the outstanding Shares, Offeror intends to take that action (if any) it deems
appropriate or advisable, including selling Shares (whether 'short' or
otherwise) in the market or tendering into any competing tender offer, so that
Offeror will not trigger the applicability of the Control Share Acquisition
Statute, the Business Combination Statute, or Subchapters E or I of Chapter 25
of the Pennsylvania Business Corporation Law (the 'PBCL').
 
     On September 14, 1998, Parent filed with the Commission a revised
preliminary Consent Statement (the 'Amended Consent Solicitation') pursuant to
which it is soliciting the consent of holders of Shares to two sets of proposals
(the 'Proposals'). The first proposal, the 'Shareholder Rights Proposal,' if
approved by the Company's shareholders, would remove from the Company Board all
powers with respect to the Rights Agreement and would vest those powers in three
individuals, the Rights Agreement Managing Agents. The Rights Agreement Managing
Agents will cause the Rights Agreement to be amended in a number of respects,
including making it inapplicable (i) to any tender or exchange offer (including
the Second Offer, as defined herein) if, as a result of that offer, the offeror
and its affiliates would be the beneficial owners of a majority of the
outstanding Shares and (ii) to any merger (including the Proposed Merger, as
defined herein) if the merger either does not require shareholder approval or is
approved by the requisite vote of the Company's shareholders. The Rights
Agreement Managing Agents will also cause the Rights Agreement to be amended to
make the Rights redeemable and to make other changes to facilitate an
acquisition of the Company by any person (including Parent). Parent believes
that the Shareholder Rights Proposal Nullification Provision is illegal and
unenforceable and is seeking judicial declaratory relief to this effect. See
Section 8 of this Second Supplement. Accordingly, Parent and Offeror intend to
continue to solicit consents to the Shareholder Rights Proposal.
 
     Parent's second set of proposals, the 'Nominee Election Proposals,' if
approved by the Company's shareholders, would result in the Nominees becoming a
majority of the Company Board. The Nominees, if elected, intend, subject to
their fiduciary duties as directors of the Company, to cause the Company to
enter into an agreement providing for a merger or similar business combination
(a 'Proposed Merger') with Parent providing for payment to the Company's
shareholders of $44.50 per Share in cash. The Proposed Merger would be subject
to the approval of at least 66 2/3% of the votes cast by all of the shareholders
of the Company entitled to vote, unless Parent shall have previously acquired
80% or more of the outstanding Shares pursuant to the Offer and the Second Offer
or otherwise. The Nominees also intend to take whatever other actions are
appropriate, subject to fulfillment of their fiduciary duties as directors of
the Company, to facilitate the Second Offer, including approving the Second
Offer and the Proposed Merger under the Business Combination Statute.
 
     THE OFFER DOES NOT CONSTITUTE A SOLICITATION OF PROXIES OR WRITTEN CONSENTS
FROM THE COMPANY'S SHAREHOLDERS. ANY SOLICITATION OF PROXIES OR WRITTEN CONSENTS
WHICH PARENT OR OFFEROR MIGHT MAKE WOULD BE MADE ONLY PURSUANT TO SEPARATE PROXY
OR CONSENT SOLICITATION MATERIALS COMPLYING WITH THE REQUIREMENTS OF SECTION
14(a) OF THE SECURITIES EXCHANGE ACT OF 1934, AS AMENDED (THE 'EXCHANGE ACT').
 
     FOLLOWING OFFEROR'S ACCEPTANCE FOR PAYMENT OF SHARES IN THE OFFER, OFFEROR
INTENDS PROMPTLY TO COMMENCE ANOTHER TENDER OFFER (THE 'SECOND OFFER') TO
PURCHASE ALL OUTSTANDING SHARES NOT OWNED BY OFFEROR AT A PRICE OF $44.50 PER
SHARE, NET TO THE SELLER IN CASH, WITHOUT INTEREST, UPON ESSENTIALLY THE SAME
TERMS AND SUBJECT TO THE SAME CONDITIONS SET FORTH IN THE OFFER TO PURCHASE IN
ORDER TO ACQUIRE CONTROL OF, AND THE ENTIRE EQUITY INTEREST IN, THE COMPANY.
HOWEVER, DEPENDING ON CIRCUMSTANCES PREVAILING AT THE TIME OF THE SECOND OFFER,
INCLUDING THEN PREVAILING INTEREST RATES, STOCK MARKET, FINANCIAL AND OTHER
ECONOMIC CONDITIONS AND THE COMPANY'S BUSINESS AND FINANCIAL CONDITION,
INCLUDING
 
                                       2

ANY FINANCIAL ENGINEERING UNDERTAKEN BY THE COMPANY, THE PRICE PER SHARE IN THAT
OFFER COULD BE HIGHER OR LOWER AND THE OTHER TERMS AND CONDITIONS OF THE SECOND
OFFER MAY BE AMENDED. SHARES ACCEPTED FOR PAYMENT UNDER THE OFFER WILL NOT
RECEIVE ANY HIGHER PRICE THAT MAY BE AVAILABLE IN THE SECOND OFFER (OR
OTHERWISE).
 
     This Second Supplement should be read in conjunction with the Offer to
Purchase as amended and supplemented by the First Supplement. Except as set
forth in this Second Supplement and the revised Letter of Transmittal, the terms
and conditions previously set forth in the Offer to Purchase as amended and
supplemented by the First Supplement and the Letters of Transmittal mailed with
the Offer to Purchase and the First Supplement remain applicable in all respects
to the Offer. Terms used but not defined in this Second Supplement have the
meanings set forth in the original Offer to Purchase as amended and supplemented
by the First Supplement.
 
     Based upon information contained in the Company's Quarterly Report on Form
10-Q for the quarter ended June 30, 1998 (the 'Company 1998 Second Quarter
10-Q'), as of July 27, 1998, 218,601,033 Shares were issued and outstanding.
Accordingly, Parent believes that the 20,000,000 Shares for which the Offer is
being made should constitute less than 10% of the outstanding Shares, which
Offeror believes is less than the number of Shares that Offeror can purchase
without becoming an 'Acquiring Person' under the Rights Agreement as amended by
the Company on September 17, 1998.
 
     THE OFFER TO PURCHASE, THE FIRST SUPPLEMENT, THIS SECOND SUPPLEMENT AND THE
REVISED LETTER OF TRANSMITTAL CONTAIN IMPORTANT INFORMATION WHICH SHOULD BE READ
CAREFULLY BEFORE ANY DECISION IS MADE WITH RESPECT TO THE OFFER.
 
     1. TERMS OF THE OFFER; PRORATION; EXPIRATION DATE. The discussion set forth
in Section 1 of the Offer to Purchase, as amended and supplemented by the First
Supplement, is hereby amended and supplemented as follows:
 
     Upon the terms and subject to the conditions of the Offer (including, if
the Offer is extended or amended, the terms and conditions of any extension or
amendment), Offeror will accept for payment and pay for up to an aggregate of
20,000,000 Shares that are validly tendered prior to the Expiration Date (as
defined herein) and not properly withdrawn in accordance with Section 4 of the
Offer to Purchase. The term 'Expiration Date' means 12:00 Midnight, New York
City time, on October 2, 1998 unless and until Offeror, in its sole discretion,
shall have extended the period of time during which the Offer is open, in which
event the term 'Expiration Date' will mean the latest time and date at which the
Offer, as so extended by Offeror, will expire.
 
     THE OFFER IS CONDITIONED UPON SATISFACTION OF THE CONDITIONS SET FORTH IN
SECTION 8 OF THE FIRST SUPPLEMENT AND SECTION 7 OF THIS SECOND SUPPLEMENT.
 
     OFFEROR RESERVES THE RIGHT (SUBJECT TO THE APPLICABLE RULES AND REGULATIONS
OF THE COMMISSION) TO AMEND OR WAIVE ANY TERMS AND CONDITIONS OF THE OFFER.
 
     If more than 20,000,000 Shares are validly tendered prior to the Expiration
Date and not properly withdrawn, Offeror will, upon the terms and subject to the
conditions of the Offer, accept for payment and pay for only 20,000,000 Shares,
on a pro rata basis, with adjustments to avoid purchases of fractional Shares,
based upon the number of Shares validly tendered prior to the Expiration Date
and not properly withdrawn. Because of the difficulty of determining precisely
the number of Shares validly tendered and not withdrawn, if proration is
required, Offeror would not expect to be able to announce the final results of
proration or pay for Shares until at least three days after the Expiration Date.
Preliminary results of proration will be announced by press release as promptly
as practicable after the Expiration Date. Holders of Shares may obtain such
preliminary information from the Information Agent and also may be able to
obtain such preliminary information from their brokers.
 
     2. PROCEDURES FOR TENDERING SHARES. The discussion set forth in Section 3
of the Offer to Purchase, as amended and supplemented by the First Supplement,
is hereby amended and supplemented as follows:
 
     TO BE VALID, A TENDER OF SHARES MUST BE ACCOMPANIED BY CERTIFICATES
REPRESENTING SHARES OR THE BOOK-ENTRY TRANSFER PROCEDURES MUST BE COMPLIED WITH
ON A TIMELY BASIS. SEE SECTION 3 OF THE OFFER TO
 
                                       3

PURCHASE. SHARES MAY NOT BE TENDERED PURSUANT TO GUARANTEED DELIVERY PROCEDURES
AFTER SEPTEMBER 14, 1998.
 
     The revised Letter of Transmittal distributed with this Second Supplement
may be used to tender Shares. Tendering shareholders also may continue to use
the Letters of Transmittal previously delivered with the Offer to Purchase and
the First Supplement to tender Shares. HOWEVER, THE PROVISIONS IN THE LETTER OF
TRANSMITTAL DISTRIBUTED WITH THE OFFER TO PURCHASE RELATING TO GUARANTEED
DELIVERY WILL NO LONGER BE APPLICABLE TO THE OFFER. By tendering Shares pursuant
to the revised Letter of Transmittal or the Letters of Transmittal previously
delivered, tendering shareholders will be deemed to represent and warrant to
Parent and Offeror that the tender of Shares complies with Rule 14e-4 under the
Exchange Act.
 
     SHAREHOLDERS WHO HAVE PREVIOUSLY VALIDLY TENDERED SHARES PURSUANT TO THE
OFFER AND WHO HAVE NOT WITHDRAWN THOSE SHARES NEED NOT TAKE ANY FURTHER ACTION
IN ORDER TO TENDER SHARES PURSUANT TO THE OFFER, AS AMENDED. SHAREHOLDERS WHO
HAVE TENDERED SHARES ON OR PRIOR TO SEPTEMBER 11, 1998 PURSUANT TO GUARANTEED
DELIVERY PROCEDURES SHOULD COMPLY WITH THE REQUIRED PROCEDURES. SEE SECTION 3 OF
THE OFFER TO PURCHASE.
 
     By executing the Letter of Transmittal, a tendering shareholder irrevocably
appoints designees of Offeror as the shareholder's attorneys-in-fact and
proxies, each with full power of substitution, in the manner set forth in the
appropriate Letter of Transmittal, to the full extent of the shareholder's right
with respect to the Shares (or, if applicable, Rights) tendered by that
shareholder and accepted for payment by Offeror (and any and all other Shares or
other securities or rights issued or issuable in respect of these Shares on or
after August 10, 1998). All powers of attorney and proxies will be considered
irrevocable and coupled with an interest in the tendered Shares. This
appointment is effective upon the acceptance for payment of Shares by Offeror in
accordance with the terms of the Offer. Upon acceptance for payment, all prior
proxies, other than any consents in favor of proposals set forth in the Consent
Solicitation, given by the shareholder with respect to these Shares or other
securities or rights will, without further action, be revoked and no subsequent
proxies may be given or written consents executed by the shareholder (and, if
given or executed, will not be deemed effective) with respect to these Shares.
The designees of Offeror will, with respect to the Shares and other securities
or rights, be empowered to exercise all voting and other rights of the
shareholder as they, in their sole judgment, deem proper in respect of any
annual or special meeting of the Company's shareholders, or any adjournment or
postponement thereof, or by written consent in lieu of any meeting or otherwise.
Offeror reserves the right to require that, in order for Shares to be deemed
validly tendered, immediately upon Offeror's payment for the Shares, Offeror or
its designee must be able to exercise full voting and other rights with respect
to the Shares and the other securities or rights issued or issuable in respect
of the Shares, including the voting of Common Stock at any shareholders meeting
(whether annual or special or whether or not adjourned) or written consents in
lieu of any meeting or otherwise.
 
     OFFEROR INTENDS TO VOTE ALL SHARES ACQUIRED IN THE OFFER IN FAVOR OF THE
PROPOSALS.
 
     3. PRICE RANGE OF COMMON STOCK; DIVIDENDS. The discussion set forth in
Section 6 of the Offer to Purchase, as amended and supplemented by the First
Supplement, is hereby amended and supplemented as follows:
 
     On September 18, 1998, the last full trading day before AlliedSignal's
public announcement of its intention to amend the Offer, the last reported
closing price of the Shares on the NYSE was $40 13/16. SHAREHOLDERS ARE URGED TO
OBTAIN A CURRENT MARKET QUOTATION FOR THE SHARES.
 
     4. SOURCE AND AMOUNT OF FUNDS. The discussion set forth in Section 10 of
the Offer to Purchase, as amended and supplemented by the First Supplement, is
hereby amended and supplemented as follows:
 
     Offeror estimates that the total amount of funds now required to acquire
Shares pursuant to the Offer and the Second Offer and to pay all related costs
and expenses, will be approximately $10.1 billion, of which approximately $1.0
billion will be required to consummate the Offer and to pay related
 
                                       4

costs and expenses. Parent anticipates borrowing up to approximately $1.0
billion by issuing commercial paper and/or engaging in either short, medium and
possibly long-term borrowings, or a combination thereof, in the bank, private
and public debt market to finance the acquisition of the Shares pursuant to the
Offer and to pay the related costs and expenses.
 
     5. BACKGROUND OF THE OFFER; CONTACTS WITH THE COMPANY. The discussion set
forth in Section 11 of the Offer to Purchase, as amended and supplemented by the
First Supplement, is hereby amended and supplemented as follows:
 
     On September 18, 1998, the Company filed with the Commission an amendment
to its Solicitation/Recommendation Statement on Schedule 14D-9, which reflected
the conclusion of the Company Board that Offeror's offer for 40,000,000 Shares
was not in the best interests of the Company and its relevant constituencies and
recommended to Company shareholders that they reject that offer.
 
     According to the Company's September 18, 1998 amendment to its
Solicitation/Recommendation Statement on Schedule 14D-9, in response to
Offeror's offer for 40,000,000 Shares and to Parent's stated intention to seek
shareholder consents to the Shareholder Rights Proposal, the Company Board
approved, at a meeting held on September 17, 1998, Amendment No. 4 to the Rights
Agreement, previously described.
 
     Parent and Offeror believe that the Shareholder Rights Proposal
Nullification Provision is invalid and unenforceable because it unlawfully
interferes with the rights of shareholders to exercise their fundamental voting
rights and unlawfully deprives shareholders of their rights under the PBCL and
the Company's articles of incorporation to limit the authority of the Company
Board. Parent is amending the AlliedSignal Complaint to seek a declaration that
the Shareholder Rights Proposal Nullification Provision is invalid and
unenforceable. See Section 8 of this Second Supplement.
 
     6. PURPOSES OF THE OFFER AND THE PROPOSED MERGER; PLANS FOR THE COMPANY;
CERTAIN CONSIDERATIONS. The discussion set forth in Section 12 of the Offer to
Purchase, as amended and supplemented by the First Supplement, is hereby amended
and supplemented as follows:
 
     The purposes of the Offer are for Parent, through Offeror, to acquire a
significant equity interest in the Company as the first step toward a business
combination of Parent and the Company and to obtain a significant vote for
purposes of the Amended Consent Solicitation. Following Offeror's acceptance for
payment of Shares in the Offer, Purchaser intends to commence the Second Offer
to acquire control of, and the entire equity interest in, the Company. The
Second Offer will be subject to essentially the same terms and conditions set
forth in the Offer to Purchase, including the Minimum Condition, the Business
Combination Condition, the Control Share Condition and the Rights Condition
(each as defined in the Offer to Purchase). However, depending on circumstances
prevailing at the time of the Second Offer, including then prevailing interest
rates, stock market, financial and other economic conditions and the Company's
business and financial condition, including any financial engineering undertaken
by the Company, the price per Share in that offer could be higher or lower and
the other terms and conditions of the Second Offer may be amended. Shares
accepted for payment under the Offer will not receive any higher price that may
be available in the Second Offer (or otherwise).
 
     THE OFFER DOES NOT CONSTITUTE A SOLICITATION OF PROXIES OR WRITTEN CONSENTS
FROM THE COMPANY'S SHAREHOLDERS. ANY SOLICITATION OF PROXIES OR WRITTEN CONSENTS
WHICH PARENT OR OFFEROR UNDERTAKES WOULD BE MADE ONLY PURSUANT TO SEPARATE PROXY
OR CONSENT SOLICITATION MATERIALS IN COMPLIANCE WITH THE REQUIREMENTS OF SECTION
14(a) OF THE EXCHANGE ACT.
 
     7. CONDITIONS OF THE OFFER. The discussion set forth in Section 14 of the
Offer to Purchase, as amended and supplemented by the First Supplement, is
hereby amended and supplemented as follows:
 
     Parent and Purchaser will not assert the condition to the Offer set forth
in paragraph (a) of Section 8 of the First Supplement as a result of the filing
on August 21, 1998 of the Company Action, but reserve the right to assert that
condition with respect to future developments with respect to the Company
Action. See Section 9 of the First Supplement.
 
                                       5

     Parent and Purchaser do not presently intend to assert the condition to the
Offer set forth in clause (iii) of paragraph (h) of Section 8 of the First
Supplement as a result of Amendment No. 4 to the Rights Agreement adopted by the
Company on September 17, 1998 but reserve the right to assert that condition if
the Shareholder Rights Proposal Nullification Provision is not invalidated or is
not otherwise inapplicable to the Shareholder Rights Proposal.
 
     In addition, Offeror hereby amends Section 8 of the First Supplement to
replace all references to 'sole judgment' and 'sole discretion' of Offeror as
related to the conditions of the Offer with references to 'reasonable judgment'
and 'reasonable discretion' of Offeror and to delete the last paragraph thereof.
Section 8 of the First Supplement, as so amended, is set forth in its entirety
as Annex I to this Second Supplement.
 
     8. CERTAIN LEGAL MATTERS; REGULATORY APPROVALS; CERTAIN LITIGATION. The
discussion set forth in Section 15 of the Offer to Purchase, as amended and
supplemented by the First Supplement, is hereby amended and supplemented as
follows:
 
     CERTAIN LITIGATION. On September 14, 1998, Parent filed its motion for (1)
partial summary judgment on its claim for a declaratory judgment in the Amended
Complaint that the Nonredemption Provision is ultra vires and invalid, or, in
the alternative, a preliminary injunction restraining enforcement of the
Nonredemption Provision; and (2) a preliminary injunction prohibiting the
Company Board from amending the Company By-laws or Rights Agreement or taking
any other action that would, as a practical matter, make the shareholder vote on
the Amended Consent Solicitation meaningless. The motion is scheduled to be
heard on September 28, 1998.
 
     On September 18, 1998, in the Company Action, Parent filed a cross-motion
for partial summary judgment to dismiss the Company's claim that Parent's
consent solicitation is unlawful. The hearings on the Company's motion for
partial summary judgment and Parent's cross-motion are also scheduled to be
heard on September 28, 1998.
 
     Parent is requesting leave to file a Second Amended Complaint in the action
it brought against the Company (the 'AlliedSignal Action'). In addition to the
relief sought in the Amended Complaint, which was filed on September 16, 1998,
the Second Amended Complaint will seek declaratory and injunctive relief with
respect to the Company's Fourth Amendment of the Rights Agreement. Parent is
filing a supplemental motion to obtain that relief and has requested that the
supplemental motion also be heard on September 28, 1998.
 
                                          PMA ACQUISITION CORPORATION
September 21, 1998                        ALLIEDSIGNAL INC.
 
                                       6

                                    ANNEX I
 
     CONDITIONS OF THE OFFER. Notwithstanding any other terms of the Offer, and
in addition to (and not in limitation of) Offeror's rights to extend and amend
the Offer at any time in its sole discretion, Offeror will not be required to
accept for payment or, subject to any applicable rules and regulations of the
Commission, including Rule 14e-1(c) under the Exchange Act (relating to
Offeror's obligation to pay for or return tendered Shares promptly after
termination or withdrawal of the Offer), pay for, and may delay the acceptance
for payment of or, subject to the restriction above, the payment for, any
tendered Shares, and may terminate the Offer as to any Shares not then paid for,
if Offeror, in its reasonable discretion, determines (1) at or prior to the
expiration of the Offer (i) the Rights have not been redeemed by the Company
Board or Offeror is not satisfied that the Rights have been invalidated or are
otherwise inapplicable to the Offer (the 'Amended Rights Condition'); (ii) the
acquisition of Shares pursuant to the Offer has not been approved pursuant to
Chapter 25, Subchapter F of the PBCL (the 'Business Combination Statute') or
Offeror is not satisfied that the Business Combination Statute is invalid or
otherwise inapplicable to the Offer (the 'Amended Business Combination
Condition'); or (iii) Offeror has not been accorded the right to vote the Shares
acquired by it pursuant to the Offer under Chapter 25, Subchapter G of the PBCL
(the 'Control Share Statute') or Offeror is not satisfied that the Control Share
Statute is invalid or otherwise inapplicable to the Offeror (the 'Amended
Control Share Statute') or (2) at any time after July 30, 1998 and prior to the
expiration of the Offer, any of the following events shall occur:
 
          (a) there shall have been threatened, instituted or pending any
     action, proceeding, application or counterclaim before any court or
     governmental regulatory or administrative agency, authority, tribunal or
     commission, domestic or foreign, by any government or governmental
     authority or agency or commission, domestic or foreign, or by any other
     person, domestic or foreign (whether brought by the Company, an affiliate
     of the Company or any other person), which (i) challenges or seeks to
     challenge or make illegal the acquisition by Parent or Offeror (or any
     affiliate thereof) of the Shares, restrains, delays or prohibits or seeks
     to restrain, delay or prohibit the making of the Offer, consummation of the
     transactions contemplated by the Offer or any other subsequent business
     combination, restrains, prohibits or seeks to restrain or prohibit the
     performance of any of the contracts or other arrangements entered into by
     Offeror or any of its affiliates in connection with the acquisition of the
     Company or obtains or seeks to obtain any material damages or otherwise
     directly or indirectly relating to the transactions contemplated by the
     Offer, (ii) prohibits or limits or seeks to prohibit or limit Parent's or
     Offeror's ownership or operation of all or any portion of their or the
     Company's business or assets (including, without limitation, the business
     or assets of their respective affiliates and subsidiaries) or compels or
     seeks to compel Parent or Offeror to dispose of or hold separate all or any
     portion of their own or the Company's business or assets (including without
     limitation the business or assets of their respective affiliates and
     subsidiaries or imposes or seeks to impose any limitation on the ability of
     Parent, Offeror or any affiliate of either of them to conduct its own
     business or own the assets as a result of the transactions contemplated by
     the Offer or any other subsequent business combination, (iii) makes or
     seeks to make the acceptance for payment, purchase of, or payment for, the
     Shares pursuant to the Offer illegal or results in a delay in, or
     restricts, the ability of Parent or Offeror, or renders Parent or Offeror
     unable, to accept for payment, purchase or pay for some or all of the
     Shares or to consummate the Offer, (iv) imposes or seeks to impose
     limitations on the ability of Parent or Offeror or any affiliate of either
     of them effectively to acquire or hold or to exercise full rights of
     ownership of the Shares, including, without limitation, the right to vote
     the Shares purchased by them on an equal basis with all other Shares on all
     matters properly presented to the shareholders of the Company, (v) in the
     reasonable judgment of Parent or Offeror, might adversely affect the
     Company or any of its subsidiaries or affiliates or Parent, Offeror, or any
     of their respective affiliates or subsidiaries, (vi) in the reasonable
     judgment of Parent or Offeror, might result in a diminution in the value of
     the Shares or the benefits expected to be derived by Parent or Offeror as a
     result of the transactions contemplated by the Offer, (vii) in the
     reasonable judgment of Parent or Offeror, imposes or seeks to impose any
     material condition to the Offer unacceptable to Parent or Offeror or
     (viii) otherwise directly or indirectly relates to the Offer or any other
     business combination with the Company;
 
                                      A-1

          (b) there shall be any action taken, or any statute, rule, regulation
     or order or injunction shall be sought, proposed, enacted, promulgated,
     entered, enforced or deemed or become applicable to (i) Parent, Offeror or
     any other affiliate of Parent or (ii) the Offer or other subsequent
     business combination between Parent or Offeror (or any affiliate thereof)
     and the Company or any affiliate of the Company or any other action shall
     have been taken, proposed or threatened, by any government, governmental
     authority or other regulatory or administrative agency or commission or
     court, domestic, foreign or supranational, that, in the reasonable judgment
     of Parent or Offeror, might, in each case, directly or indirectly, result
     in any of the consequences referred to in clauses (i) through (viii) of
     paragraph (a) above;
 
          (c) any change (or any condition, event or development involving a
     prospective change) shall have occurred or been threatened in the business,
     properties, assets, liabilities, capitalization, shareholders' equity,
     condition (financial or otherwise), operations, licenses, franchises,
     permits, permit applications, results of operations or prospects of the
     Company or any of its subsidiaries or affiliates which, in the reasonable
     judgment of Parent or Offeror, is or may be materially adverse to the
     Company or any of its subsidiaries or affiliates, or Parent or Offeror
     shall have become aware of any fact which, in the reasonable judgment of
     Parent or Offeror, has or may have material adverse significance with
     respect to either the value of the Company or any of its subsidiaries or
     the value of the Shares to Parent, Offeror or any other affiliate thereof;
 
          (d) there shall have occurred or been threatened (i) any general
     suspension of trading in, or limitation on prices for, securities on any
     national securities exchange or in the over-the-counter market in the
     United States, (ii) any extraordinary or material adverse change in the
     financial markets or major stock exchange indices in the United States or
     abroad or in the market price of Shares, (iii) any change in the general
     political, market, economic or financial conditions in the United States or
     abroad that could, in the reasonable judgment of Offeror, have a material
     adverse effect upon the business, properties, assets, liabilities,
     capitalization, stockholders' equity, condition (financial or otherwise),
     operations, licenses or franchises, results of operations or prospects of
     the Company or material change in United States currency exchange rates or
     a suspension of, or limitation on, the markets therefor, (iv) a declaration
     of a banking moratorium or any suspension of payments in respect of banks
     in the United States, (v) any limitation (whether or not mandatory) by any
     government, domestic, foreign or supranational, or governmental entity on,
     or other event that, in the reasonable judgment of Offeror, might affect,
     the extension of credit by banks or other lending institutions, (vi) a
     commencement of a war or armed conflict or hostilities or other national or
     international calamity directly or indirectly involving the United States
     or (vii) in the case of any of the foregoing existing at the time of the
     commencement of the Offer, a material acceleration or worsening thereof;
 
          (e) other than the redemption of the Rights at the Redemption Price
     (as defined in Section 8 of the Offer to Purchase), the Company shall have
     (i) issued, distributed, pledged, sold or authorized, proposed or announced
     the issuance of or sale, distribution or pledge to any person of (A) any
     shares of its capital stock (other than sales or issuances pursuant to
     options outstanding on July 30, 1998 in accordance with their terms as
     disclosed on that date of the Shares or securities convertible into shares
     or any rights, warrants or options to acquire shares or convertible
     securities or any other securities of the Company) or (B) any other
     securities in respect of, in lieu of or in substitution for Shares
     outstanding on July 30, 1998, (ii) purchased, acquired or otherwise caused
     a reduction in the number of, or proposed or offered to purchase, acquire
     or otherwise reduce the number of, any outstanding Shares or other
     securities, (iii) declared, paid or proposed to declare or pay any dividend
     or distribution on Shares (other than regular quarterly dividends on the
     Shares not in excess of $0.27 per Share, and with record and payment dates,
     in accordance with recent practice) or on any other security or issued,
     authorized, recommended or proposed the issuance or payment of any other
     distribution in respect of the Shares whether payable in cash, securities
     or other property, (iv) altered or proposed to alter any material term of
     any outstanding security, (v) incurred any debt other than in the ordinary
     course of business and consistent with past practice or any debt containing
     burdensome covenants, (vi) issued, sold or authorized or announced or
     proposed the issuance of or sale to any person of any debt securities or
     any securities convertible into or exchangeable for debt securities or any
     rights, warrants or options entitling the holder
 
                                      A-2

     thereof to purchase or otherwise acquire any debt securities or incurred or
     announced its intention, to incur any debt other than in the ordinary
     course of business and consistent with past practice, (vii) split, combined
     or otherwise changed, or authorized or proposed the split, combination or
     other change of the Shares or its capitalization, (viii) authorized,
     recommended, proposed or entered into or publicly announced its intent to
     enter into any consolidation, liquidation, dissolution, acquisition or
     disposition of a material amount of assets or securities, any material
     change in its capitalization, any waiver, release or relinquishment of any
     material contract rights or comparable right of the Company or any of its
     subsidiaries or any agreement contemplating any of the foregoing or any
     comparable event not in the ordinary course of business, or taken any
     action to implement any transaction previously authorized, recommended,
     proposed or publicly announced, (ix) after September 10, 1998, transferred
     into escrow any amounts required to fund any existing benefit, employment
     or severance agreements with any of its employees or entered into any
     employment, severance or similar agreement, arrangement or plan with any of
     its employees other than in the ordinary course of business and consistent
     with past practice or entered into or amended any agreements, arrangements
     or plans so as to provide for increased benefits to the employees as a
     result of or in connection with the transactions contemplated by the Offer
     or any other change in control of the Company, (x) except as may be
     required by law, taken any action to terminate or amend any employee
     benefit plan (as defined in Section 3(2) of ERISA) of the Company, or
     Parent or Offeror shall have become aware of any action which was not
     previously disclosed in publicly available filings, (xi) except as
     contemplated by the Offer, amended or proposed or authorized any amendment
     to its articles of incorporation or bylaws or similar organizational
     documents, (xii) authorized, recommended, proposed or entered into any
     other transaction that in the reasonable judgment of Parent or Offeror
     could, individually or in the aggregate, adversely affect the value of the
     Shares to Parent or Offeror or (xiii) agreed in writing or otherwise to
     take any of the foregoing actions or Parent or Offeror shall have learned
     about any action which has not previously been publicly disclosed by the
     Company and also set forth in filings with the Commission;
 
          (f) a tender or exchange offer for any Shares shall be made or
     publicly proposed to be made by any other person (including the Company or
     any of its subsidiaries or affiliates) or it shall be publicly disclosed or
     Offeror shall otherwise learn that (i) any person, entity (including the
     Company or any of its subsidiaries) or 'group' (within the meaning of
     Section 13(d)(3) of the Exchange Act) shall have acquired or proposed to
     acquire beneficial ownership of more than 5% of any class or series of
     capital stock of the Company (including the Shares), through the
     acquisition of stock, the formation of a group or otherwise, or shall have
     been granted any right, option or warrant, conditional or otherwise, to
     acquire beneficial ownership of more than 5% of any class or series of
     capital stock of the Company (including the Shares) other than acquisitions
     for bona fide arbitrage purposes only and except as disclosed in a Schedule
     13D or Schedule 13G on file with the Commission on the date of this Offer
     to Purchase, (ii) any such person, entity or group which, before the date
     of this Offer to Purchase, had filed such a Schedule with the Commission,
     has acquired or proposes to acquire, through the acquisition of stock, the
     formation of a group or otherwise, beneficial ownership of an additional 1%
     or more of any class or series of capital stock of the Company (including
     the Shares), or shall have been granted any right, option or warrant,
     conditional or otherwise, to acquire beneficial ownership of an additional
     1% or more of any class or series of capital stock of the Company
     (including the Shares), (iii) any person or group shall enter into a
     definitive agreement or an agreement in principle or make a proposal with
     respect to a tender offer or exchange offer or a merger, consolidation or
     other business combination with or involving the Company or (iv) any person
     shall file a Notification and Report Form under the Hart-Scott-Rodino Act
     or make a public announcement reflecting an intent to acquire the Company
     or any assets or securities of the Company;
 
          (g) the Company and Parent or Offeror shall have reached an agreement
     or understanding that the Offer be terminated or amended or Parent or
     Offeror (or one of their respective affiliates) shall have entered into a
     definitive agreement or an agreement in principle to acquire the Company by
     merger or similar business combination;
 
                                      A-3

          (h) Parent or Offeror shall become aware (i) that any material
     contractual right of the Company or any of its subsidiaries or affiliates
     shall be impaired or otherwise adversely affected or that any material
     amount of indebtedness of the Company of any of its subsidiaries shall
     become accelerated or otherwise become due prior to its stated due date, in
     either case with or without notice or the lapse of time or both, as a
     result of the transactions contemplated by the Offer, (ii) of any covenant,
     term or condition in any of the Company's or any of its subsidiaries'
     instruments or agreements that are or may be materially adverse to the
     value of the Shares in the hands of Offeror or any other affiliate of
     Parent (including, but not limited to, any event of default that may ensue
     as a result of the consummation of the Offer or any other business
     combination or the acquisition of control of the Company) or (iii) other
     than amendments publicly announced by the Company prior to September 10,
     1998, the Rights Agreement shall have been amended in any material respect;
     or
 
          (i) Parent or Offeror shall not have obtained any waiver, consent,
     extension, approval, action or non-action from any governmental authority
     or agency which in its judgment is necessary to consummate the Offer,
 
which, in the reasonable judgment of Parent or Offeror in any case, and
regardless of the circumstances (including any action or inaction by Parent or
Offeror or any of their affiliates) giving rise to any condition, makes it
inadvisable to proceed with the Offer and/or with acceptance for payment or
payment for Shares.
 
     The foregoing conditions are for the sole benefit of Parent and Offeror and
may be asserted by Parent and Offeror in their reasonable discretion regardless
of the circumstances giving rise to any conditions or may be waived by Parent or
Offeror in their reasonable discretion in whole or in part at any time and from
time to time. The failure by Parent or Offeror at any time to exercise any of
the foregoing rights will not be deemed a waiver of any right and each right
shall be deemed an ongoing right which may be asserted at any time and from time
to time. Any determination by Parent or Offeror concerning any condition or
event described in Section 14, as amended, shall be final and binding upon all
parties.
 
                                      A-4

                      [THIS PAGE INTENTIONALLY LEFT BLANK]

     Facsimile copies of the Letters of Transmittal, properly completed and duly
executed, will be accepted. The Letters of Transmittal, certificates for Shares
and any other required documents should be sent or delivered by each shareholder
of the Company or his broker, dealer, commercial bank, trust company or other
nominee to the Depositary at one of its addresses set forth below:
 
                        The Depositary for the Offer is:
 
                              THE BANK OF NEW YORK

                                                                     
                                                  By Facsimile:                  By Hand/Overnight Courier:
                                        (For Eligible Institutions Only)        Tender & Exchange Department
                                                 (212) 815-6213                      101 Barclay Street
                                                                                 Receive and Deliver Window
                                              Confirm by telephone:                 New York, N.Y. 10286
               By Mail:                          1-800-507-9357
     Tender & Exchange Department
            P.O. Box 11248
         Church Street Station
       New York, N.Y. 10286-1248

     Questions and requests for assistance may be directed to the Information
Agent or the Dealer Managers, at their respective addresses and telephone
numbers set forth below. Additional copies of this Second Supplement, the First
Supplement, the Offer to Purchase, the Letters of Transmittal and other tender
offer materials may be obtained from the Information Agent as set forth below,
and will be furnished promptly at Offeror's expense. You may also contact your
broker, dealer, commercial bank, trust company or other nominee for assistance
concerning the Offer.
 
                    The Information Agent for the Offer is:
 
                               MORROW & CO., INC.
 
                                445 Park Avenue
                                   5th Floor
                            New York, New York 10022
                            Toll Free (800) 566-9061
                    Banks and Brokerage Firms, please call:
                                 (800) 662-5200
 
                     The Dealer Managers for the Offer are:

                                                      
                LAZARD FRERES & CO. LLC                                   GOLDMAN, SACHS & CO.
                 30 Rockefeller Plaza                                        85 Broad Street
               New York, New York 10020                                 New York, New York 10004
             (212) 632-6717 (call collect)                                   (800) 323-5678

                             LETTER OF TRANSMITTAL
                        TO TENDER SHARES OF COMMON STOCK
            (INCLUDING THE ASSOCIATED COMMON STOCK PURCHASE RIGHTS)
                                       OF
                                AMP INCORPORATED
                       PURSUANT TO THE OFFER TO PURCHASE
                             DATED AUGUST 10, 1998
                          AS AMENDED AND SUPPLEMENTED
                            BY THE FIRST SUPPLEMENT
                            DATED SEPTEMBER 14, 1998
                          AND BY THE SECOND SUPPLEMENT
                            DATED SEPTEMBER 21, 1998
                                       BY
                          PMA ACQUISITION CORPORATION
                          A WHOLLY OWNED SUBSIDIARY OF
                               ALLIEDSIGNAL INC.
 
     THE OFFER AND WITHDRAWAL RIGHTS HAVE BEEN EXTENDED. THE OFFER, WITHDRAWAL
RIGHTS AND PRORATION PERIOD WILL EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY TIME,
ON FRIDAY, OCTOBER 2, 1998, UNLESS THE OFFER IS EXTENDED.
 
                                The Depositary:
 
                              THE BANK OF NEW YORK

                                                                                          
                 By Mail:                                 By Facsimile:                         By Hand/Overnight Courier:
       Tender & Exchange Department              (For Eligible Institutions Only)              Tender & Exchange Department
              P.O. Box 11248                              (212) 815-6213                            101 Barclay Street
          Church Street Station                       Confirm by telephone:                     Receive and Deliver Window
        New York, N.Y. 10286-1248                         1-800-507-9357                           New York, N.Y. 10286

     DELIVERY OF THIS LETTER OF TRANSMITTAL TO AN ADDRESS, OR TRANSMISSION OF
INSTRUCTIONS BY FACSIMILE, OTHER THAN AS SET FORTH ABOVE, DOES NOT CONSTITUTE A
VALID DELIVERY. YOU MUST SIGN THIS LETTER OF TRANSMITTAL IN THE APPROPRIATE
SPACE THEREFOR PROVIDED BELOW AND COMPLETE THE SUBSTITUTE FORM W-9 SET FORTH
BELOW.
 
     THE INSTRUCTIONS ACCOMPANYING THIS LETTER OF TRANSMITTAL SHOULD BE READ
CAREFULLY BEFORE THIS LETTER OF TRANSMITTAL IS COMPLETED.
 
     This Letter of Transmittal or one of the Letters of Transmittal previously
delivered to shareholders is to be used either if certificates for Shares and,
if applicable, Rights (as such terms are defined below) are to be forwarded
herewith or, unless an Agent's Message (as defined below) is utilized, if
delivery of Shares and, if applicable, Rights is to be made by book-entry
transfer (in the case of Rights, if available) to an account maintained by the
Depositary at a Book-Entry Transfer Facility (as defined in Section 2 of the
Offer to Purchase, dated August 10, 1998 (the 'Offer to Purchase')) and pursuant
to the procedures set forth in Section 3 of the Offer to Purchase, as amended by
the First Supplement to the Offer to Purchase, dated September 14, 1998 (the
'First Supplement') and by the Second Supplement to the Offer to Purchase, dated
September 21, 1998 (the 'Second Supplement') or delivery of Shares is to be made
using DRS (as defined below). UNLESS THE AMENDED RIGHTS CONDITION (AS DEFINED IN
THE FIRST SUPPLEMENT) IS SATISFIED, SHAREHOLDERS WILL BE REQUIRED TO TENDER ONE
RIGHT FOR EACH SHARE TENDERED IN ORDER TO EFFECT A VALID TENDER OF SHARES.
UNLESS THE DISTRIBUTION DATE (AS DEFINED IN THE OFFER TO PURCHASE) OCCURS, A
TENDER OF SHARES WILL ALSO CONSTITUTE A TENDER OF THE ASSOCIATED RIGHTS.
 
     SHAREHOLDERS WHO HAVE PREVIOUSLY VALIDLY TENDERED SHARES PURSUANT TO THE
OFFER AND WHO HAVE NOT WITHDRAWN THOSE SHARES NEED NOT TAKE ANY FURTHER ACTION
IN ORDER TO TENDER SHARES PURSUANT TO THE OFFER, AS AMENDED. SHAREHOLDERS WHO
HAVE TENDERED SHARES ON OR PRIOR TO SEPTEMBER 11, 1998

PURSUANT TO GUARANTEED DELIVERY PROCEDURES SHOULD COMPLY WITH THE REQUIRED
PROCEDURES. SEE SECTION 3 OF THE OFFER TO PURCHASE.
 
     SHARES MAY NOT BE TENDERED PURSUANT TO GUARANTEED DELIVERY PROCEDURES AFTER
SEPTEMBER 14, 1998.
 
     DELIVERY OF DOCUMENTS TO A BOOK-ENTRY TRANSFER FACILITY DOES NOT CONSTITUTE
DELIVERY TO THE DEPOSITARY.

                                                                                                      
- -------------------------------------------------------------------------------------------------------------------------------
                                                   DESCRIPTION OF SHARES TENDERED
- -------------------------------------------------------------------------------------------------------------------------------
        NAME(S) AND ADDRESS(ES) OF REGISTERED HOLDER(S)                                    SHARES TENDERED
                  (PLEASE FILL IN, IF BLANK)                                    (ATTACH ADDITIONAL LIST IF NECESSARY)
- -------------------------------------------------------------------------------------------------------------------------------
                                                                                               NUMBER
                                                                         SHARE                OF SHARES              NUMBER OF
                                                                      CERTIFICATE          REPRESENTED BY             SHARES
                                                                      NUMBER(S)*           CERTIFICATE(S)*          TENDERED**
                                                               ----------------------------------------------------------------
                                                               ----------------------------------------------------------------
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                                                               ----------------------------------------------------------------
                                                                     TOTAL SHARES
- -------------------------------------------------------------------------------------------------------------------------------
 
If you hold your Shares through direct registration, check this box and write your DRS number and the number of Shares tendered
by DRS in space provided. [ ]
                                                 DRS Number ...................................................................
                                                 Number of Shares held through DRS ............................................
- -------------------------------------------------------------------------------------------------------------------------------
  *Need not be completed by shareholders tendering by book-entry transfer.
- -------------------------------------------------------------------------------------------------------------------------------
**Unless otherwise indicated, it will be assumed that all Shares represented by any certificates delivered to the Depositary are
  being tendered. See Instruction 4.
- -------------------------------------------------------------------------------------------------------------------------------

 
                                       2

 

- -------------------------------------------------------------------------------------------------------------------------------
                                                  DESCRIPTION OF RIGHTS TENDERED*
- -------------------------------------------------------------------------------------------------------------------------------
      NAME(S) AND ADDRESS(ES) OF REGISTERED HOLDER(S)                                      RIGHTS TENDERED
                 (PLEASE FILL IN, IF BLANK)                                     (ATTACH ADDITIONAL LIST IF NECESSARY)
- -------------------------------------------------------------------------------------------------------------------------------
                                                                                               NUMBER
                                                                        RIGHTS                OF RIGHTS              NUMBER OF
                                                                      CERTIFICATE          REPRESENTED BY             RIGHTS
                                                                      NUMBER(S)**         CERTIFICATE(S)**          TENDERED***
                                                               ----------------------------------------------------------------
                                                               ----------------------------------------------------------------
                                                               ----------------------------------------------------------------
                                                               ----------------------------------------------------------------
                                                               ----------------------------------------------------------------
                                                               ----------------------------------------------------------------
                                                               ----------------------------------------------------------------
                                                               ----------------------------------------------------------------
                                                                     TOTAL RIGHTS
- -------------------------------------------------------------------------------------------------------------------------------
  *Need not be completed if Distribution Date has not occurred.
 **If the tendered Rights are represented by separate certificates, complete using the certificate numbers of such certificates
   for Rights. If the tendered Rights are not represented by separate certificates, or if such certificates have not been
   distributed, complete using the certificate numbers of the Shares with respect to which the Rights were issued.
***Unless otherwise indicated, it will be assumed that all Rights described above are being tendered. See Instruction 4.
- -------------------------------------------------------------------------------------------------------------------------------

                                       3

                    NOTE: SIGNATURES MUST BE PROVIDED BELOW
              PLEASE READ THE ACCOMPANYING INSTRUCTIONS CAREFULLY
 
[ ] CHECK HERE IF TENDERED SHARES ARE BEING DELIVERED BY BOOK-ENTRY TRANSFER TO
    THE DEPOSITARY'S ACCOUNT AT ONE OF THE BOOK-ENTRY TRANSFER FACILITIES AND
    COMPLETE THE FOLLOWING:
 
   Name of Tendering Institution  ..............................................
   Account No.   ............................................................ at
             [ ] The Depository Trust Company
   Transaction Code No.  .......................................................
 
                                       4

Ladies and Gentlemen:
 
     The undersigned hereby tenders to PMA Acquisition Corporation, a Delaware
corporation (the 'Offeror'), a wholly owned subsidiary of AlliedSignal Inc., a
Delaware corporation (the 'Parent'), the above-described shares of Common Stock,
without par value (the 'Shares'), of AMP Incorporated, a Pennsylvania
corporation (the 'Company'), together with an equal number of any associated
Common Stock Purchase Rights (the 'Rights') issued pursuant to the Rights
Agreement, as amended (the 'Rights Agreement'), between the Company and
ChaseMellon Shareholder Services L.L.C., as Rights Agent, upon the terms and
subject to the conditions set forth in the Offer to Purchase, dated August 10,
1998 (the 'Offer to Purchase'), as amended by the First Supplement to the Offer
of Purchase, dated September 14, 1998 (the 'First Supplement') and by the Second
Supplement to the Offer to Purchase, dated September 21, 1998 (the 'Second
Supplement') and in this Letter of Transmittal (which, together with any
amendments or supplements thereto, collectively constitute the 'Offer'), receipt
of which is hereby acknowledged.
 
     Upon the terms of the Offer, subject to, and effective upon, acceptance for
payment of, and payment for, the Shares and, if applicable, Rights tendered
herewith in accordance with the terms of the Offer, the undersigned hereby
sells, assigns and transfers to, or upon the order of, the Offeror all right,
title and interest in and to all the Shares and, if applicable, Rights that are
being tendered hereby (and any and all other Shares, Rights or other securities
or rights issued or issuable in respect thereof on or after August 10, 1998),
and irrevocably constitutes and appoints The Bank of New York (the
'Depositary'), the true and lawful agent and attorney-in-fact of the
undersigned, with full power of substitution (such power of attorney being
deemed to be an irrevocable power coupled with an interest), to the full extent
of the undersigned's rights with respect to such Shares and, if applicable,
Rights (and any such other Shares, Rights or securities or rights), to (a)
deliver certificates for such Shares and Rights (and any such other Shares,
Rights or securities or rights) or transfer ownership of such Shares and Rights
(and any such other Shares, Rights or securities or rights) on the account books
maintained by a Book-Entry Transfer Facility together, in any such case, with
all accompanying evidences of transfer and authenticity to, or upon the order
of, the Offeror, (b) in the case of participants in the Direct Registration
System ('DRS'), to place a stop against the Shares held under DRS and, following
expiration of the Offer, to instruct the Transfer Agent to transfer such Shares,
(c) present such Shares and Rights (and any such other Shares, Rights or
securities or rights) for transfer on the Company's books and (d) receive all
benefits and otherwise exercise all rights of beneficial ownership of such
Shares and Rights (and any such other Shares, Rights or securities or rights),
all in accordance with the terms of the Offer.
 
     The undersigned hereby represents and warrants that the undersigned has
full power and authority to tender, sell, assign and transfer the tendered
Shares and, if applicable, Rights (and any and all other Shares, Rights or other
securities or rights issued or issuable in respect of such Shares or Rights on
or after August 10, 1998) and, when the same are accepted for payment by the
Offeror, the Offeror will acquire good title thereto, free and clear of all
liens, restrictions, claims and encumbrances, and the same will not be subject
to any adverse claim. The undersigned will, upon request, execute any additional
documents deemed by the Depositary or the Offeror to be necessary or desirable
to complete the sale, assignment and transfer of the tendered Shares and Rights
(and any and all other Shares, Rights or other securities or rights issued or
issuable in respect thereof on or after August 10, 1998).
 
     THE UNDERSIGNED UNDERSTANDS THAT, UNLESS THE AMENDED RIGHTS CONDITION (AS
DEFINED IN THE FIRST SUPPLEMENT) IS SATISFIED, SHAREHOLDERS WILL BE REQUIRED TO
TENDER ONE RIGHT FOR EACH SHARE TENDERED IN ORDER TO EFFECT A VALID TENDER OF
SHARES IN ACCORDANCE WITH THE PROCEDURES SET FORTH IN SECTION 3 OF THE OFFER TO
PURCHASE, AS AMENDED. If the Distribution Date occurs and separate certificates
representing the Rights are distributed to holders of Shares prior to the time
Shares are tendered herewith, certificates representing a number of Rights equal
to the number of Shares being tendered herewith must be delivered to the
Depositary or, if available, a Book-Entry Confirmation must be received by the
Depositary with respect thereto, in order for such Shares tendered herewith to
be validly tendered. If the Distribution Date occurs and separate certificates
representing the Rights are not distributed prior to the time Shares are
tendered herewith, a tender of
 
                                       5

Shares constitutes an agreement by the tendering shareholder to deliver
certificates representing a number of Rights equal to the number of Shares
tendered pursuant to the Offer to the Depositary within a period ending three
New York Stock Exchange trading days after the date certificates representing
the Rights are distributed, or a Book-Entry Confirmation with respect to Rights
(the 'Rights Delivery Period'). However, after expiration of the Rights Delivery
Period, the Offeror may elect to reject as invalid a tender of Shares with
respect to which certificates for, or a Book-Entry Confirmation with respect to,
an equal number of Rights has not been received by the Depositary. Nevertheless,
Offeror will be entitled to accept for payment Shares tendered by the
undersigned prior to the receipt of the certificates for the Rights required to
be tendered with such Shares, or a Book-Entry Confirmation with respect to such
Rights, and either (a), subject to complying with the applicable rules and
regulations of the Securities and Exchange Commission, withhold payment for such
Shares pending receipt of the certificates for, or a Book-Entry Confirmation
with respect to, such Rights or (b) make payment for Shares accepted for payment
pending receipt of the certificates for, or a Book-Entry Confirmation with
respect to, such Rights in reliance upon the agreement of a tendering
shareholder to deliver Rights. Any determination by the Offeror to make payment
for Shares in reliance upon such agreement or, after the expiration of the
Rights Delivery Period, to reject a tender as invalid will be made in the sole
and absolute discretion of the Offeror.
 
     All authority conferred or agreed to be conferred pursuant to this Letter
of Transmittal shall be binding upon the successors, assigns, heirs, executors,
administrators and legal representatives of the undersigned and shall not be
affected by, and shall survive, the death or incapacity of the undersigned.
Except as stated in the Offer to Purchase, as amended, this tender is
irrevocable.
 
     The undersigned hereby irrevocably appoints designees of Offeror as the
attorneys-in-fact and proxies, each with full power of substitution, to the full
extent of the shareholder's right with respect to the Shares (or, if applicable,
Rights) tendered by the undersigned and accepted for payment by Offeror (and any
and all other Shares or other securities or rights issued or issuable in respect
of these Shares on or after August 10, 1998). All powers of attorney and proxies
will be considered irrevocable and coupled with an interest in the tendered
Shares. This appointment is effective upon the acceptance for payment of Shares
by Offeror in accordance with the terms of the Offer. Upon acceptance for
payment, all prior proxies, other than any consents in favor of proposals set
forth in the Consent Solicitation given by the undersigned with respect to these
Shares or other securities or rights will, without further action, be revoked
and no subsequent proxies may be given or written consents executed by the
undersigned (and, if given or executed, will not be deemed effective) with
respect for these Shares. The designees of Offeror will, with respect to the
Shares and other securities or rights, be empowered to exercise all voting and
other rights of the undersigned as they, in their sole judgment, deem proper in
respect of any annual or special meeting of the Company's shareholders, or any
adjournment or postponement thereof, or by written consent in lieu of any
meeting or otherwise. Offeror reserves the right to require that, in order for
Shares to be deemed validly tendered, immediately upon Offeror's payment for the
Shares, Offeror or its designee must be able to exercise full voting and other
rights with respect to the Shares and the other securities or rights issued or
issuable in respect of the Shares, including the voting of Common Stock at any
shareholders meeting (whether annual or special or whether or not adjourned) or
written consents in lieu of any meeting or otherwise.
 
     The undersigned understands that the valid tender of Shares and, if
applicable, Rights pursuant to any of the procedures described in Section 3 of
the Offer to Purchase, as amended, and in the Instructions hereto, will
constitute a binding agreement between the undersigned and the Offeror upon the
terms and subject to the conditions of the Offer. Without limiting the
foregoing, if the price to be paid in the Offer is amended in accordance with
the Offer, the price to be paid to the undersigned will be the amended price
notwithstanding the fact that a different price is stated in this Letter of
Transmittal.
 
     Unless otherwise indicated herein under 'Special Payment Instructions',
please issue the check for the purchase price and/or return any certificates for
Shares or Rights not tendered or accepted for payment in the name(s) of the
registered holder(s) appearing under 'Description of Shares Tendered' and
'Description of Rights Tendered', respectively. Similarly, unless otherwise
indicated under 'Special Delivery Instructions', please mail the check for the
purchase price and/or return any certificates for
 
                                       6

Shares or Rights not tendered or accepted for payment (and accompanying
documents, as appropriate) to the address(es) of the registered holder(s)
appearing under 'Description of Shares Tendered' and 'Description of Rights
Tendered', respectively. In the event that both the Special Delivery
Instructions and the Special Payment Instructions are completed, please issue
the check for the purchase price and/or return any certificates for Shares or
Rights not tendered or accepted for payment (and any accompanying documents, as
appropriate) in the name of, and deliver such check and/or return such
certificates (and any accompanying documents, as appropriate) to, the person or
persons so indicated. Unless otherwise indicated herein under 'Special Payment
Instructions', please credit any Shares and Rights tendered herewith by
book-entry transfer that are not accepted for payment by crediting the account
at the Book-Entry Transfer Facility designated above. The undersigned recognizes
that the Offeror has no obligation pursuant to the Special Payment Instructions
to transfer any Shares or Rights from the name of the registered holder thereof
if the Offeror does not accept for payment any of the Shares or Rights,
respectively, so tendered.
 
                          SPECIAL PAYMENT INSTRUCTIONS
                        (SEE INSTRUCTIONS 1, 5, 6 AND 7)
 
     To be completed ONLY if the check for the purchase price of Shares or
   Rights purchased or certificates for Shares or Rights not tendered or not
   purchased are to be issued in the name of someone other than the
   undersigned, or if Shares or Rights tendered by book-entry transfer that
   are not purchased are to be returned by credit to an account at one of the
   Book-Entry Transfer Facilities other than that designated above.
 
   Issue check and/or certificates to:
 
   Name  ....................................................................
                                 (PLEASE PRINT)
 
   Address  .................................................................
 
    .........................................................................
                              (INCLUDING ZIP CODE)
 
    .........................................................................
                         (TAXPAYER IDENTIFICATION NO.)
 
                           (SEE SUBSTITUTE FORM W-9)
 
   [ ] Credit unpurchased Shares or Rights tendered by book-entry transfer to
       the account set forth below:
 
    .........................................................................
                             NAME OF ACCOUNT PARTY
 
    .........................................................................
                                  ACCOUNT NO.
 
   [ ] The Depository Trust Company
                         SPECIAL DELIVERY INSTRUCTIONS
                        (SEE INSTRUCTIONS 1, 5, 6 AND 7)
 
     To be completed ONLY if the check for the purchase price of Shares or
   Rights purchased or certificates for Shares or Rights not tendered or not
   purchased are to be mailed to someone other than the undersigned or to the
   undersigned at an address other than that shown below the undersigned's
   signature(s).
 
   Mail check and/or certificates to:
 
   Name  ....................................................................
                                 (PLEASE PRINT)
 
   Address  .................................................................
 
    .........................................................................
                              (INCLUDING ZIP CODE)
 
    .........................................................................
                         (TAXPAYER IDENTIFICATION NO.)

                                       7

 
                                     SIGN HERE
 
                       (COMPLETE SUBSTITUTE FORM W-9 BELOW)
 
    ............................................................................
 
    ............................................................................
                             SIGNATURE(S) OF OWNER(S)
 
    ............................................................................
 
   Name(s) .....................................................................
 
    ............................................................................
 
   Capacity (full title) .......................................................
 
   Address .....................................................................
 
    ............................................................................
 
    ............................................................................
                               (INCLUDING ZIP CODE)
    ............................................................................
 
   Area Code and Telephone Number ..............................................
 
   Taxpayer Identification Number ..............................................
 
   Dated: ............................................................... , 1998
 
   (Must be signed by registered holder(s) exactly as name(s) appear(s) on stock
   certificate(s) or on a security position listing or by the person(s)
   authorized to become registered holder(s) by certificates and documents
   transmitted herewith. If signature is by a trustee, executor, administrator,
   guardian, attorney-in-fact, agent, officer of a corporation or other person
   acting in a fiduciary or representative capacity, please set forth full title
   and see Instruction 5).
 
   If a participant in the Direct Registration System ('DRS'), the person(s)
   signing above hereby directs the Transfer Agent to place a stop against the
   aforementioned number of Shares held through DRS pending the expiration of
   the Offer. Upon expiration of the Offer, the Transfer Agent is further
   directed to follow the directions for delivery to the Depositary.
 
                             GUARANTEE OF SIGNATURE(S)
                            (SEE INSTRUCTIONS 1 AND 5)
 
   FOR USE BY FINANCIAL INSTITUTIONS ONLY. PLACE MEDALLION GUARANTEE IN SPACE
   BELOW.
 
   Authorized signature(s) .....................................................
 
   Name ........................................................................
 
   Name of Firm ................................................................
 
   Address .....................................................................
 
    ............................................................................
                                               (INCLUDING ZIP CODE)
   Area Code and Telephone Number ..............................................
 
   Dated: ............................................................... , 1998
 
                                       8

 

- -------------------------------------------------------------------------------------------------------------------------------
                                            PAYOR'S NAME: THE BANK OF NEW YORK
- -------------------------------------------------------------------------------------------------------------------------------
   SUBSTITUTE                    PART 1 -- PLEASE PROVIDE YOUR TIN IN THE BOX AT    PART III -- Social Security Number
                                 RIGHT AND CERTIFY BY SIGNING AND DATING BELOW      or Employer Identification
                                                                                    Number
                                                                                          -------------------------------
                                                                                    (If awaiting TIN write 'Applied For')
FORM W-9                         ----------------------------------------------------------------------------------------
DEPARTMENT OF THE TREASURY       PART II -- For Payees exempt from backup withholding, see the enclosed Guidelines for
INTERNAL REVENUE SERVICE         Certification of Taxpayer Identification Number on Substitute Form W-9 and complete as
                                 instructed therein.
 
                                 Certification -- Under penalties of perjury, I certify that:
 
PAYOR'S REQUEST                  (1) The number shown on this form is my correct TIN (or I am waiting for a number to
FOR TAXPAYER                     be issued to me); and
IDENTIFICATION 
NUMBER ('TIN')                   (2) I am not subject to backup withholding either because I have not been notified by
                                 the Internal Revenue Service (IRS) that I am subject to backup withholding as a result
                                     of a failure to report all interest or dividends, or the IRS has notified me that
                                     I am no longer subject to backup withholding.
 
                                 CERTIFICATION INSTRUCTIONS -- You must cross out Item (2) above if you have been
                                 notified by the IRS that you are subject to backup withholding because of
                                 underreporting interest or dividends on your tax return. However, if after being
                                 notified by the IRS that you were subject to backup withholding, you received another
                                 notification from the IRS that you were no longer subject to backup withholding, do
                                 not cross out item (2). (Also see instructions in the enclosed Guidelines).
                                 ----------------------------------------------------------------------------------------------
                                 SIGNATURE ...................................  DATE ..................................
- -------------------------------------------------------------------------------------------------------------------------------

NOTE: FAILURE TO COMPLETE AND RETURN THIS SUBSTITUTE FORM W-9 MAY RESULT IN
      BACKUP WITHHOLDING OF 31% OF ANY PAYMENTS MADE TO YOU PURSUANT TO THE
      OFFER. PLEASE REVIEW THE ENCLOSED GUIDELINES FOR CERTIFICATION OF TAXPAYER
      IDENTIFICATION NUMBER ON SUBSTITUTE FORM W-9 FOR ADDITIONAL DETAILS.
 
      YOU MUST COMPLETE THE FOLLOWING CERTIFICATE IF YOU ARE AWAITING YOUR TIN.
 
- --------------------------------------------------------------------------------
             CERTIFICATE OF AWAITING TAXPAYER IDENTIFICATION NUMBER
 
     I certify under penalties of perjury that a TIN has not been issued to me,
and either (1) I have mailed or delivered an application to receive a TIN to the
appropriate IRS Center or Social Security Administration Office or (2) I intend
to mail or deliver an application in the near future. I understand that if I do
not provide a TIN by the time of payment, 31% of all payments pursuant to the
Offer made to me thereafter will be withheld until I provide a number.
 
Signature ...............................    Date ..............................
- --------------------------------------------------------------------------------
 
                                       9

                                  INSTRUCTIONS
             FORMING PART OF THE TERMS AND CONDITIONS OF THE OFFER
 
1. GUARANTEE OF SIGNATURES.
 
     No signature guarantee is required on this Letter of Transmittal (a) if
this Letter of Transmittal is signed by the registered holder(s) (which term,
for purposes of this Section, includes any participant in any of the Book-Entry
Transfer Facilities' systems whose name appears on a security position listing
as the owner of the Shares) of Shares and Rights tendered herewith, unless such
registered holder(s) has completed either the box entitled 'Special Payment
Instructions' or the box entitled 'Special Delivery Instructions' on the Letter
of Transmittal or (b) if such Shares and Rights are tendered for the account of
a financial institution (including most commercial banks, savings and loan
associations and brokerage houses) that is a participant in the Security
Transfer Agents Medallion Program, the New York Stock Exchange Medallion
Signature Guarantee Program or the Stock Exchange Medallion Program (an
'Eligible Institution'). In all other cases, all signatures on this Letter of
Transmittal must be guaranteed by an Eligible Institution. See Instruction 5.
 
2. DELIVERY OF LETTER OF TRANSMITTAL AND SHARES.
 
     This Letter of Transmittal is to be completed by shareholders either if
certificates are to be forwarded herewith or, unless an Agent's Message is
utilized, if delivery of Shares and, if applicable, Rights is to be made
pursuant to the procedures for book-entry transfer set forth in Section 3 of the
Offer to Purchase or if delivery of Shares is to be made pursuant to DRS. For a
shareholder validly to tender Shares and Rights pursuant to the Offer, a
properly completed and duly executed Letter of Transmittal (or facsimile
thereof), together with any required signature guarantees, or, in the case of a
book-entry transfer, an Agent's Message, and any other required documents, must
be received by the Depositary at one of its addresses set forth herein prior to
the Expiration Date and either certificates for tendered Shares and Rights must
be received by the Depositary at one of such addresses or Shares and Rights must
be delivered pursuant to the procedures for book-entry transfer set forth herein
(and a Book-Entry Confirmation received by the Depositary), in each case prior
to the Expiration Date.
 
     UNLESS THE AMENDED RIGHTS CONDITION IS SATISFIED, SHAREHOLDERS WILL BE
REQUIRED TO TENDER ONE RIGHT FOR EACH SHARE TENDERED IN ORDER TO EFFECT A VALID
TENDER OF SHARES. Unless the Distribution Date occurs, a tender of Shares will
also constitute a tender of the associated Rights. If the Distribution Date
occurs and separate certificates representing the Rights are distributed prior
to the time Shares are tendered herewith, certificates representing a number of
Rights equal to the number of Shares being tendered herewith must be delivered
to the Depositary or, if available, a Book-Entry Confirmation must be received
by the Depositary with respect thereto, in order for such Shares tendered
herewith to be validly tendered. If the Distribution Date occurs and separate
certificates representing the Rights are not distributed prior to the time
Shares are tendered herewith, a tender of Shares constitutes an agreement by the
tendering shareholder to deliver certificates representing a number of Rights
equal to the number of Shares tendered pursuant to the Offer to the Depositary
within a period ending three New York Stock Exchange trading days after the date
certificates representing the Rights are distributed, or a Book-Entry
Confirmation with respect to Rights. SHARES MAY NOT BE TENDERED PURSUANT TO
GUARANTEED DELIVERY PROCEDURES AFTER SEPTEMBER 14, 1998.
 
     The term 'Agent's Message' means a message, transmitted by a Book-Entry
Transfer Facility to, and received by, the Depositary and forming a part of a
Book-Entry Confirmation, which states that such Book-Entry Transfer Facility has
received an express acknowledgment from the participant in such Book-Entry
Transfer Facility tendering the Shares that such participant has received and
agrees to be bound by the terms of the Letter of Transmittal and that the
Purchaser may enforce such agreement against the participant.
 
     The signatures on this Letter of Transmittal cover the Shares and the
Rights tendered hereby whether or not such Rights are delivered simultaneously
with such Shares.
 
     THE METHOD OF DELIVERY OF SHARES, RIGHTS, THE LETTER OF TRANSMITTAL AND ALL
OTHER REQUIRED DOCUMENTS, INCLUDING DELIVERY THROUGH ANY BOOK-ENTRY TRANSFER
FACILITY, IS AT THE ELECTION AND RISK OF THE TENDERING SHAREHOLDER. SHARES WILL
BE DEEMED DELIVERED ONLY WHEN ACTUALLY RECEIVED BY THE DEPOSITARY (INCLUDING, IN
THE CASE OF A BOOK-ENTRY TRANSFER, BY BOOK-ENTRY CONFIRMATION). IF DELIVERY IS
BY MAIL, REGISTERED MAIL WITH RETURN RECEIPT REQUESTED, PROPERLY
 
                                       10

INSURED, IS RECOMMENDED. IN ALL CASES, SUFFICIENT TIME SHOULD BE ALLOWED TO
ENSURE TIMELY DELIVERY.
 
     No alternative, conditional or contingent tenders will be accepted and no
fractional Shares or Rights will be purchased. All tendering shareholders, by
execution of this Letter of Transmittal (or facsimile hereof), waive any right
to receive any notice of the acceptance of their Shares or Rights for payment.
 
3. INADEQUATE SPACE.
 
     If the space provided herein is inadequate, the certificate numbers and/or
the number of Shares or Rights should be listed on a separate schedule attached
hereto.
 
4. PARTIAL TENDERS (NOT APPLICABLE TO STOCKHOLDERS WHO TENDER BY BOOK-ENTRY
TRANSFER).
 
     If fewer than all the Shares or Rights evidenced by any certificate
submitted are to be tendered, fill in the number of Shares or Rights that are to
be tendered in the box entitled 'Number of Shares Tendered' or 'Number of Rights
Tendered', as appropriate. In any such case, new certificate(s) for the
remainder of the Shares or Rights that were evidenced by the old certificate(s)
will be sent to the registered holder, unless otherwise provided in the
appropriate box on this Letter of Transmittal, as soon as practicable after the
acceptance for payment of, and payment for, the Shares and Rights tendered
herewith. All Shares and Rights represented by certificates delivered to the
Depositary will be deemed to have been tendered unless otherwise indicated.
 
5. SIGNATURES ON LETTER OF TRANSMITTAL; STOCK POWERS AND ENDORSEMENTS.
 
     If this Letter of Transmittal is signed by the registered holder of the
Shares and Rights tendered hereby, the signature must correspond with the name
as written on the face of the certificate(s) without any change whatsoever.
 
     If any of the Shares or Rights tendered hereby are owned of record by two
or more joint owners, all such owners must sign this Letter of Transmittal.
 
     If any tendered Shares or Rights are registered in different names on
several certificates, it will be necessary to complete, sign and submit as many
separate Letters of Transmittal as there are different registrations of
certificates.
 
     If this Letter of Transmittal or any certificates or stock powers are
signed by trustees, executors, administrators, guardians, attorneys-in-fact,
officers of corporations or others acting in a fiduciary or representative
capacity, such persons should so indicate when signing, and proper evidence
satisfactory to the Offeror of their authority so to act must be submitted.
 
     When this Letter of Transmittal is signed by the registered owner(s) of the
Shares and Rights listed and transmitted hereby, no endorsements of certificates
or separate stock powers are required unless payment or certificates for Shares
or Rights not tendered or accepted for payment are to be issued to a person
other than the registered owner(s). Signatures on such certificates or stock
powers must be guaranteed by an Eligible Institution.
 
     If this Letter of Transmittal is signed by a person other than the
registered owner(s) of the certificates listed, the certificates must be
endorsed or accompanied by appropriate stock powers, in either case signed
exactly as the name or names of the registered owner or owners appear on the
certificates. Signatures on such certificates or stock powers must be guaranteed
by an Eligible Institution.
 
6. STOCK TRANSFER TAXES.
 
     The Offeror will pay any stock transfer taxes with respect to the transfer
and sale of Shares or Rights to it or its order pursuant to the Offer. If,
however, payment of the purchase price is to be made to, or if certificates for
Shares or Rights not tendered or accepted for payment are to be registered in
the name of, any person(s) other than the registered holder(s), or if tendered
certificates are registered in the name(s) of any person(s) other than the
person(s) signing this Letter of Transmittal, the amount of any stock transfer
taxes (whether imposed on the registered holder(s) or such person(s)) payable on
account of the transfer to such person(s) will be deducted from the purchase
price unless satisfactory evidence of the payment of such taxes or exemption
therefrom is submitted.
 
                                       11

     EXCEPT AS PROVIDED IN THIS INSTRUCTION 6, IT WILL NOT BE NECESSARY FOR
TRANSFER TAX STAMPS TO BE AFFIXED TO THE CERTIFICATES LISTED IN THIS LETTER OF
TRANSMITTAL.
 
7. SPECIAL PAYMENT AND DELIVERY INSTRUCTION.
 
     If a check is to be issued in the name of, and/or certificates for Shares
or Rights not accepted for payment are to be returned to, a person other than
the signer of this Letter of Transmittal or if a check is to be sent and/or such
certificates are to be returned to a person other than the signer of this Letter
of Transmittal or to an address other than that shown above, the appropriate
boxes on this Letter of Transmittal should be completed.
 
8. WAIVER OF CONDITIONS.
 
     The Offeror reserves the absolute right in its sole discretion to waive any
of the specified conditions of the Offer, in whole or in part, in the case of
any Shares or Rights tendered.
 
9. 31% BACKUP WITHHOLDING.
 
     In order to avoid 'backup withholding' of federal income tax on payments of
cash pursuant to the Offer, a shareholder surrendering Shares in the Offer must,
unless an exemption applies, provide the Depositary with such shareholder's
correct taxpayer identification number ('TIN') on Substitute Form W-9 in this
Letter of Transmittal and certify under penalty of perjury that such TIN is
correct and that such shareholder is not subject to backup withholding. If a
shareholder does not provide such shareholder's correct TIN or fails to provide
the certifications described above, the Internal Revenue Service (the 'IRS') may
impose a $50 penalty on such shareholder and payment of cash to such shareholder
pursuant to the Offer may be subject to backup withholding of 31%.
 
     Backup withholding is not an additional income tax. Rather, the amount of
the backup withholding can be credited against the Federal income tax liability
of the person subject to the backup withholding, provided that the required
information is given to the IRS. If backup withholding results in an overpayment
of tax, a refund can be obtained by the shareholder upon filing an income tax
return.
 
     The shareholder is required to give the Depositary the TIN (i.e., social
security number or employer identification number) of the record owner of the
Shares. If the Shares are held in more than one name or are not in the name of
the actual owner, consult the enclosed 'Guidelines for Certification of Taxpayer
Identification Number on Substitute Form W-9' for additional guidance on which
number to report.
 
     The box in Part III of the Substitute Form W-9 may be checked if the
tendering shareholder has not been issued a TIN and has applied for a TIN or
intends to apply for a TIN in the near future. If the box in Part III is
checked, the shareholder or other payee must also complete the Certificate of
Awaiting Taxpayer Identification Number below in order to avoid backup
withholding. Notwithstanding that the box in Part III is checked and the
Certificate of Awaiting Taxpayer Identification Number is completed, the
Depositary will withhold 31% on all payments made prior to the time a properly
certified TIN is provided to the Depositary. However, such amounts will be
refunded to such shareholder if a TIN is provided to the Depositary within 60
days.
 
     Certain shareholders (including, among others, all corporations and certain
foreign individuals and entities) are not subject to backup withholding.
Noncorporate foreign shareholders should complete and sign the main signature
form and a Form W-8, Certificate of Foreign Status, a copy of which may be
obtained from the Depositary, in order to avoid backup withholding. See the
enclosed 'Guidelines for Certification of Taxpayer Identification Number on
Substitute Form W-9' for more instructions.
 
10. REQUESTS FOR ASSISTANCE OR ADDITIONAL COPIES.
 
     Questions and requests for assistance or additional copies of the Offer to
Purchase, the First Supplement, the Second Supplement, the Letter of
Transmittal, and the Guidelines for Certification of Taxpayer Identification
Number on Substitute Form W-9 may be directed to the Information Agent or the
Dealer Managers at their respective addresses set forth below.
 
                                       12

11. LOST, DESTROYED OR STOLEN CERTIFICATES.
 
     If any certificate representing Shares or Rights has been lost, destroyed
or stolen, the shareholder should promptly notify the Depositary by checking the
box immediately preceding the special payment/special delivery instructions and
indicating the number of Shares or Rights lost. The shareholder will then be
instructed as to the steps that must be taken in order to replace the
certificate. This Letter of Transmittal and related documents cannot be
processed until the procedures for replacing lost or destroyed certificates have
been followed.
 
     IMPORTANT: THIS LETTER OF TRANSMITTAL OR A MANUALLY SIGNED FACSIMILE COPY
HEREOF (TOGETHER WITH CERTIFICATES OR CONFIRMATION OF BOOK-ENTRY TRANSFER AND
ALL OTHER REQUIRED DOCUMENTS) MUST BE RECEIVED BY THE DEPOSITARY ON OR PRIOR TO
THE EXPIRATION DATE (AS DEFINED IN THE SECOND SUPPLEMENT).
 
                           IMPORTANT TAX INFORMATION
 
     Under federal income tax law, a shareholder whose tendered Shares or Rights
are accepted for payment is required to provide the Depositary with such
stockholder's correct TIN on the Substitute Form W-9. If such shareholder is an
individual, the TIN is such stockholder's social security number. If the
Depositary is not provided with the correct TIN, the shareholder may be subject
to a $50 penalty imposed by the Internal Revenue Service. In addition, payments
that are made to such shareholder with respect to Shares purchased pursuant to
the Offer may be subject to backup withholding.
 
     Certain shareholders (including, among others, all corporations and certain
foreign individuals) are not subject to these backup withholding and reporting
requirements. In order for a foreign individual to qualify as an exempt
recipient, that stockholder must submit a statement, signed under penalty of
perjury, attesting to that individual's exempt status. Such statements may be
obtained from the Depositary. All exempt recipients (including foreign persons
wishing to qualify as exempt recipients) should see the enclosed Guidelines for
Certification of Taxpayer Identification Number on Substitute Form W-9 for
additional instructions.
 
     If backup withholding applies, the Depositary is required to withhold 31%
of any payments made to the stockholder. Backup withholding is not an additional
tax. Rather, the tax liability of persons subject to backup withholding will be
reduced by the amount of tax withheld. If backup withholding results in an
overpayment of taxes, a refund may be obtained.
 
PURPOSE OF SUBSTITUTE FORM W-9
 
     To prevent backup federal income tax withholding on payments that are made
to a stockholder with respect to Shares purchased pursuant to the Offer, the
stockholder is required to notify the Depositary of his or her correct TIN by
completing the form certifying that the TIN provided on the Substitute Form W-9
is correct.
 
WHAT NUMBER TO GIVE THE DEPOSITARY
 
     The stockholder is required to give the Depositary the social security
number or employer identification number of the record owner of the Shares. If
the Shares are in more than one name or are not in the name of the actual owner,
consult the enclosed Guidelines for Certification of Taxpayer Identification
Number on Substitute Form W-9 for additional guidelines on which number to
report.
 
                                       13

                    The Information Agent for the Offer is:
 
                               MORROW & CO., INC.
 
                                445 Park Avenue
                                   5th Floor
                            New York, New York 10022
                            Toll Free (800) 566-9061
                          Call Collect (212) 754-8000
                                      (or)
                           Banks and Brokerage Firms.
                                  Please Call:
                                 (800) 662-5200
 
                     The Dealer Managers for the Offer are:

                                                             
                   LAZARD FRERES & CO. LLC                                           GOLDMAN, SACHS & CO.
                     30 Rockefeller Plaza                                              85 Broad Street
                   New York, New York 10020                                        New York, New York 10004

September 21, 1998

 

        LAZARD FRERES & CO. LLC                   GOLDMAN, SACHS & CO.
          30 Rockefeller Plaza                       85 Broad Street
        New York, New York 10020                New York, New York 10004

                          PMA ACQUISITION CORPORATION
                          A WHOLLY OWNED SUBSIDIARY OF
                               ALLIEDSIGNAL INC.
                                HAS AMENDED ITS
                           OFFER TO PURCHASE FOR CASH
             AND IS NOW OFFERING TO PURCHASE UP TO AN AGGREGATE OF
                       20,000,000 SHARES OF COMMON STOCK
            (INCLUDING THE ASSOCIATED COMMON STOCK PURCHASE RIGHTS)
                                       OF
                                AMP INCORPORATED
                                       AT
                              $44.50 NET PER SHARE
 
     THE OFFER AND WITHDRAWAL RIGHTS HAVE BEEN EXTENDED. THE OFFER, WITHDRAWAL
RIGHTS AND PRORATION PERIOD WILL EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY TIME,
ON FRIDAY, OCTOBER 2, 1998, UNLESS THE OFFER IS EXTENDED.
 
                                                              September 21, 1998
 
To Brokers, Dealers, Commercial Banks,
  Trust Companies and Other Nominees:
 
     We have been appointed by PMA Acquisition Corporation, a Delaware
corporation ('Offeror') and a wholly owned subsidiary of AlliedSignal Inc., a
Delaware corporation ('Parent'), to act as financial advisors and Dealer
Managers in connection with Offeror's offer to purchase up to an aggregate of
20,000,000 shares of common stock, without par value (the 'Shares'), and the
associated Common Stock Purchase Rights (the 'Rights'), of AMP Incorporated, a
Pennsylvania corporation (the 'Company'), at a purchase price of $44.50 per
Share, net to the seller in cash, without interest, upon the terms and subject
to the conditions set forth in the Offer to Purchase, dated August 10, 1998 (the
'Offer to Purchase'), as amended by the First Supplement to the Offer to
Purchase, dated September 14, 1998 and by the Second Supplement to the Offer to
Purchase, dated September 21, 1998 and in the related Letter of Transmittal
(which together constitute the 'Offer') enclosed herewith.
 
     Holders of Shares will be required to tender one Right for each Share
tendered to effect a valid tender of a Share. Unless and until the Distribution
Date (as defined in Section 8 of the Offer to Purchase) occurs, the Rights are
represented by and transferred with the Shares. Accordingly, if the Distribution
Date does not occur prior to the Expiration Date of the Offer, a tender of
Shares will constitute a tender of the associated Rights. If a Distribution Date
has occurred, certificates representing a number of Rights equal to the number
of Shares being tendered must be delivered to the Depositary in order for the
Shares to be validly tendered in accordance with the procedures described in
Section 3 of the Offer to Purchase, as amended. If a Distribution Date has
occurred, a tender of Shares without Rights constitutes an agreement by the
tendering shareholder to deliver certificates representing a number of Rights
equal to the number of Shares tendered pursuant to the Offer to the Depositary
within a period ending three New York Stock Exchange trading days after the date
certificates for Rights are distributed to shareholders, all as provided in
Section 3 of the Offer to Purchase, as amended. Offeror reserves the right to
require that it receive these certificates prior to accepting Shares for
payment. Payment for Shares tendered and purchased pursuant to the Offer will be
made only after timely receipt by the Depositary of, among other things, these
certificates, if the certificates have been distributed to holders of Shares.
Offeror will not pay any additional consideration for the Rights tendered
pursuant to the Offer.
 
     Please furnish copies of the enclosed materials to those of your clients
for whose accounts you hold Shares in your name or in the name of your nominee.

     THE OFFER, AS AMENDED, IS NO LONGER SUBJECT TO THE MINIMUM CONDITION (AS
DEFINED IN THE OFFER TO PURCHASE). IT IS CONDITIONAL UPON CERTAIN OTHER TERMS
AND CONDITIONS CONTAINED IN THE FIRST SUPPLEMENT, AS AMENDED BY THE SECOND
SUPPLEMENT.
 
     Enclosed herewith for your information and forwarding to your clients are
copies of the following documents:
 
          1. The Second Supplement, dated September 21, 1998.
 
          2. The Letter of Transmittal to tender Shares and, if applicable,
     Rights for your use and for the information of your clients. Facsimile
     copies of the Letter of Transmittal (with manual signatures) may be used to
     tender Shares and, if applicable, Rights.
 
          3. A printed form of letter which may be sent to your clients for
     whose accounts you hold Shares and/or Rights registered in your name or in
     the name of your nominee, with space provided for obtaining such clients'
     instructions with regard to the Offer.
 
          4. Guidelines of the Internal Revenue Service for Certification of
     Taxpayer Identification Number on Substitute Form W-9.
 
          5. Return envelope addressed to the Depositary.
 
     YOUR PROMPT ACTION IS REQUESTED. WE URGE YOU TO CONTACT YOUR CLIENTS AS
PROMPTLY AS POSSIBLE. PLEASE NOTE THAT THE OFFER, WITHDRAWAL RIGHTS AND
PRORATION PERIOD EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY TIME, ON FRIDAY,
OCTOBER 2, 1998, UNLESS THE OFFER IS EXTENDED.
 
     In order to accept the Offer, an appropriate duly executed and properly
completed Letter of Transmittal and any required signature guarantees, or an
Agent's Message (as defined in the Offer to Purchase) in connection with a
book-entry delivery of Shares and/or Rights and any other documents required by
the Letter of Transmittal should be sent to the Depositary and either Share and,
if applicable, Rights Certificates representing the tendered Shares and Rights
should be delivered to the Depositary, or, in the case of book-entry delivery of
Shares or Rights, such Shares or Rights should be tendered by book-entry
transfer into the Depositary's account maintained at one of the Book Entry
Transfer Facilities (as described in the Offer to Purchase), all in accordance
with the instructions set forth in the Letter of Transmittal and the Offer to
Purchase as amended by the First Supplement and the Second Supplement.
 
     SHARES MAY BE TENDERED ONLY BY THE PROPER EXECUTION AND COMPLETION OF THE
LETTER OF TRANSMITTAL. SHARES MAY NOT BE TENDERED PURSUANT TO GUARANTEED
DELIVERY PROCEDURES AFTER SEPTEMBER 14, 1998.
 
     SHAREHOLDERS WHO HAVE PREVIOUSLY VALIDLY TENDERED SHARES PURSUANT TO THE
OFFER AND WHO HAVE NOT WITHDRAWN THOSE SHARES NEED NOT TAKE ANY FURTHER ACTION
IN ORDER TO TENDER SHARES PURSUANT TO THE OFFER, AS AMENDED. SHAREHOLDERS WHO
HAVE TENDERED SHARES ON OR PRIOR TO SEPTEMBER 11, 1998 PURSUANT TO GUARANTEED
DELIVERY PROCEDURES SHOULD COMPLY WITH THE REQUIRED PROCEDURES. SEE SECTION 3 OF
THE OFFER TO PURCHASE.
 
     Offeror will not pay any commissions or fees to any broker, dealer or other
person (other than the Dealer Managers and the Information Agent, as described
in Offer to Purchase) for soliciting tenders of Shares and/or Rights pursuant to
the Offer. Offeror will, however, upon request, reimburse you for customary
clerical and mailing expenses incurred by you in forwarding any of the enclosed
materials to your clients. Offeror will pay or cause to be paid any stock
transfer taxes payable on the transfer of Shares and/or Rights to it, except as
otherwise provided in Instruction 6 of the Letter of Transmittal.
 
                                       2

     Any inquiries you may have with respect to the Offer should be addressed
to, and additional copies of the enclosed material may be obtained from, the
Dealer Managers or the Information Agent, at their respective addresses and
telephone numbers set forth on the back cover of the Offer to Purchase.
 
                             Very truly yours,
                             LAZARD FRERES & CO. LLC        GOLDMAN, SACHS & CO.
 
     NOTHING CONTAINED HEREIN OR IN THE ENCLOSED DOCUMENTS SHALL CONSTITUTE YOU
OR ANY OTHER PERSON THE AGENT OF THE PARENT, THE OFFEROR, THE DEPOSITARY, THE
INFORMATION AGENT OR ANY AFFILIATE OF ANY OF THEM, OR AUTHORIZE YOU OR ANY OTHER
PERSON TO MAKE ANY STATEMENT OR USE ANY DOCUMENT ON BEHALF OF ANY OF THEM IN
CONNECTION WITH THE OFFER OTHER THAN THE ENCLOSED DOCUMENTS AND THE STATEMENTS
CONTAINED THEREIN.
 
                                       3

            GUIDELINES FOR CERTIFICATION OF TAXPAYER IDENTIFICATION
                         NUMBER ON SUBSTITUTE FORM W-9
 
     GUIDELINES FOR DETERMINING THE PROPER IDENTIFICATION NUMBER TO GIVE THE
PAYER. Social Security numbers have nine digits separated by two hyphens: i.e.,
000-00-0000. Employer identification numbers have nine digits separated by only
one hyphen: i.e., 00-0000000. The table below will help determine the number to
give the payer.

                                   GIVE THE TAXPAYER
FOR THIS TYPE OF ACCOUNT:          IDENTIFICATION
                                   NUMBER OF --
- -----------------------------------------------------
                                
1. An individual's account         The individual
2. Two or more individuals (joint  The actual owner of the
   account)                        account or, if combined
                                   funds, the first
                                   individual on the
                                   account(1)
3. Custodian account of a minor    The minor(2)
   (Uniform Gift to Minors Act)
4. A.The usual revocable savings   The grantor- trustee(1)
      trust (grantor is also
      trustee)
   B.So-called trust account that  The actual owner(1)
     is not a legal or valid
     trust under state law
5. Sole proprietorship             The owner(3)
6. A valid trust, estate, or       The legal entity (Do not
   pension trust                   furnish the identifying
                                   number of the personal
                                   representative or
                                   trustee unless the legal
                                   entity itself is not
                                   designated in the
                                   account title.)(4)

                                   GIVE THE TAXPAYER
FOR THIS TYPE OF ACCOUNT:          IDENTIFICATION
                                   NUMBER OF --
- -----------------------------------------------------
                                
 7. Corporate account              The corporation
 8. Religious, charitable, or      The organization
    educational organization
    account
 9. Partnership account            The partnership
10. Association, club, or other    The organization
    tax-exempt organization
11. A broker or registered         The broker or nominee
    nominee
12. Account with the Department    The public entity
    of Agriculture in the name of
    a public entity (such as a
    state or local government,
    school district, or prison)
    that receives agricultural
    program payments

(1) List first and circle the name of the person whose number you furnish. If
    only one person on a joint account has an SSN, that person's number must be
    furnished.
 
(2) Circle the minor's name and furnish the minor's social security number.
 
(3) Show your individual name. You may also enter your business or 'doing
    business as' name. You may use either your social security number or your
    employer identification number.
 
(4) List first and circle the name of the legal trust, estate, or pension trust.
 
NOTE: If no name is circled when there is more than one name listed, the number
will be considered to be that of the first name listed.

            GUIDELINES FOR CERTIFICATION OF TAXPAYER IDENTIFICATION
                         NUMBER ON SUBSTITUTE FORM W-9
 
           NOTE: SECTION REFERENCES ARE TO THE INTERNAL REVENUE CODE
                             UNLESS OTHERWISE NOTED.
                                     PAGE 2
 
OBTAINING A NUMBER
 
If you do not have a taxpayer identification number or you don't know your
number, obtain Form SS-5, Application for a Social Security Number Card (for
individuals), or Form SS-4, Application for Employer Identification Number (for
businesses and all other entities), at the local office of the Social Security
Administration or the Internal Revenue Service (the 'IRS') and apply for a
number.
 
PAYEES AND PAYMENTS EXEMPT FROM BACKUP WITHHOLDING
 
The following is a list of payees exempt from backup withholding and for which
no information reporting is required. For interest and dividends, all listed
payees are exempt except item (9). For broker transactions, payees listed in
items (1) through (13) and a person registered under the Investment Advisors Act
of 1940 who regularly acts as a broker are exempt. Payments subject to reporting
under sections 6041 and 6041A are generally exempt from backup withholding only
if made to payees described in items (1) through (7), except a corporation
(other than certain hospitals described in Regulations section 1.6041-3(c)) that
provides medical and health care services or bills and collects payments for
such services is not exempt from backup withholding or information reporting.
Only payees described in items (1) through (5) are exempt from backup
withholding for barter exchange transactions and patronage dividends.
 
 (1) An organization exempt from tax under section 501(a), or an IRA, or a
     custodial account under section 403(b)(7), if the account satisfies the
     requirements of section 401(f)(2).
 
 (2) The United States or any of its agencies or instrumentalities.
 
 (3) A state, the District of Columbia, a possession of the United States, or
     any of their political subdivisions or instrumentalities.
 
 (4) A foreign government or any of its political subdivisions, agencies or
     instrumentalities.
 
 (5) An international organization or any of its agencies or instrumentalities.
 
 (6) A corporation.
 
 (7) A foreign central bank of issue.
 
 (8) A dealer in securities or commodities required to register in the United
     States, the District of Columbia or a possession of the United States.
 
 (9) A futures commission merchant registered with the Commodity Futures Trading
     Commission.
 
(10) A real estate investment trust.
 
(11) An entity registered at all times during the tax year under the Investment
     Company Act of 1940.
 
(12) A common trust fund operated by a bank under section 584(a).
 
(13) A financial institution.
 
(14) A middleman known in the investment community as a nominee or listed in the
     most recent publication of the American Society of Corporate Secretaries,
     Inc., Nominee List.
 
(15) A trust exempt from tax under section 664 or described in section 4947.
 
Payments of dividends and patronage dividends that generally are exempt from
backup withholding include the following:
 
   Payments to nonresident aliens subject to withholding under section 1441.
   Payments to partnerships not engaged in a trade or business in the U.S. and
   which have at least one nonresident partner.
 
   Payments of patronage dividends not paid in money.
 
   Payments made by certain foreign organizations.
 
   Section 404(k) payments made by an ESOP.
 
Payments of interest that generally are exempt from backup withholding include
the following:
 
   Payments of interest on obligations issued by individuals. Note: You may be
   subject to backup withholding if this interest is $600 or more and is paid in
   the course of the payer's trade or business and you have not provided your
   correct taxpayer identification number to the payer.
 
   Payments of tax-exempt interest (including exempt-interest dividends under
   section 852).
 
   Payments described in section 6049(b)(5) to nonresident aliens.
 
   Payments on tax-free covenant bonds under section 1451.
 
   Payments made by certain foreign organizations.
 
   Payments of mortgage interest to you.
 
Exempt payees described above should file substitute Form W-9 to avoid possible
erroneous backup withholding. FILE THIS FORM WITH THE PAYER, FURNISH YOUR
TAXPAYER IDENTIFICATION NUMBER, WRITE 'EXEMPT' ON THE FACE OF THE FORM, SIGN AND
DATE THE FORM AND RETURN IT TO THE PAYER. IF YOU ARE A NON-RESIDENT ALIEN OR A
FOREIGN ENTITY NOT SUBJECT TO BACKUP WITHHOLDING, FILE WITH PAYER A COMPLETED
INTERNAL REVENUE FORM W-8 (CERTIFICATE OF FOREIGN STATUS).
 
Payments that are not subject to information reporting are also not subject to
backup withholding. For details, see sections 6041, 6041A, 6042, 6044, 6045,
6049, 6050A and 6050N and the regulations promulgated thereunder.
 
PRIVACY ACT NOTICE. Section 6109 requires most recipients of dividends,
interest, or other payments to give taxpayer identification numbers to payers
who must report the payments to the IRS. The IRS uses the numbers for
identification purposes. Payers must generally withhold 31% of taxable interest,
dividends and certain other payments to a payee who does not furnish a taxpayer
identification number to a payer. Certain penalties may also apply.
 
PENALTIES
 
(1) PENALTY FOR FAILURE TO FURNISH TAXPAYER IDENTIFICATION NUMBER. If you fail
to furnish your correct taxpayer identification number to a requester, you are
subject to a penalty of $50 for each such failure unless your failure is due to
reasonable cause and not to willful neglect.
 
(2) CIVIL PENALTY FOR FALSE INFORMATION WITH RESPECT TO WITHHOLDING. If you make
a false statement with no reasonable basis which results in no imposition of
backup withholding, you are subject to a penalty of $500.
 
(3) CRIMINAL PENALTY FOR FALSIFYING INFORMATION. Willfully falsifying
certifications or affirmations may subject you to criminal penalties including
fines and/or imprisonment.
 
FOR ADDITIONAL INFORMATION CONTACT YOUR TAX CONSULTANT OR THE INTERNAL REVENUE
SERVICE.
 
[ ] By checking this box, all Old Debentures held by you for our account will be
tendered in the Exchange Offer. If fewer than all Old Debentures are to be
tendered, we have checked the box below and indicated the principal amount of
Old Debentures to be tendered by you.
 
[ ] $ _________Old Debentures*
 
* Unless otherwise indicated, it will be assumed that all such Old Debentures
  are to be tendered.

                          PMA ACQUISITION CORPORATION
                          A WHOLLY OWNED SUBSIDIARY OF
                               ALLIEDSIGNAL INC.
                                HAS AMENDED ITS
                           OFFER TO PURCHASE FOR CASH
             AND IS NOW OFFERING TO PURCHASE UP TO AN AGGREGATE OF
                       20,000,000 SHARES OF COMMON STOCK
            (INCLUDING THE ASSOCIATED COMMON STOCK PURCHASE RIGHTS)
                                       OF
                                AMP INCORPORATED
                                       AT
                                $44.50 PER SHARE
- --------------------------------------------------------------------------------
     THE OFFER AND WITHDRAWAL RIGHTS HAVE BEEN EXTENDED. THE OFFER, WITHDRAWAL
RIGHTS AND PRORATION PERIOD WILL EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY TIME,
ON FRIDAY, OCTOBER 2, 1998, UNLESS THE OFFER IS EXTENDED.
- --------------------------------------------------------------------------------
 
                                                              September 21, 1998
 
To Our Clients:
 
     Enclosed for your consideration is the Second Supplement, dated September
21, 1998 (the 'Second Supplement') to the Offer to Purchase, dated August 10,
1998 (the 'Offer to Purchase'), as amended by the First Supplement, dated
September 14, 1998 (the 'First Supplement'), and the related Letter of
Transmittal (which as may be amended or supplemented from time to time,
collectively constitute the 'Offer') relating to an offer by PMA Acquisition
Corporation, a Delaware corporation ('Offeror'), and a wholly owned subsidiary
of AlliedSignal Inc., a Delaware corporation ('Parent'), to purchase up to an
aggregate of 20,000,000 shares of common stock, without par value (the
'Shares'), and the associated Common Stock Purchase Rights (the 'Rights'), of
AMP Incorporated, a Pennsylvania corporation (the 'Company'), at a purchase
price of $44.50 per Share, net to the seller in cash (the 'Offer Price'),
without interest, upon the terms and subject to the conditions set forth in the
Offer.
 
     Holders of Shares will be required to tender one Right for each Share
tendered to effect a valid tender of a Share. Unless and until the Distribution
Date (as defined in Section 8 of the Offer to Purchase) occurs, the Rights are
represented by and transferred with the Shares. Accordingly, if the Distribution
Date does not occur prior to the Expiration Date of the Offer, a tender of
Shares will constitute a tender of the associated Rights. If a Distribution Date
has occurred, certificates representing a number of Rights equal to the number
of Shares being tendered must be delivered to the Depositary in order for the
Shares to be validly tendered in accordance with the procedures described in
Section 3 of the Offer to Purchase, as amended. If a Distribution Date has
occurred, a tender of Shares without Rights constitutes an agreement by the
tendering shareholder to deliver certificates representing a number of Rights
equal to the number of Shares tendered pursuant to the Offer to the Depositary
within a period ending three New York Stock Exchange trading days after the date
certificates for Rights are distributed to shareholders, all as provided in
Section 3 of the Offer to Purchase, as amended. Offeror reserves the right to
require that it receive these certificates prior to accepting Shares for
payment. Payment for Shares tendered and purchased pursuant to the Offer will be
made only after timely receipt by the Depositary of, among other things, these
certificates, if the certificates have been distributed to holders of Shares.
Offeror will not pay any additional consideration for the Rights tendered
pursuant to the Offer.
 
     SHARES MAY BE TENDERED ONLY BY THE PROPER EXECUTION AND COMPLETION OF THE
LETTER OF TRANSMITTAL. SHARES MAY NOT BE TENDERED PURSUANT TO GUARANTEED
DELIVERY PROCEDURES AFTER SEPTEMBER 14, 1998.

     SHAREHOLDERS WHO HAVE PREVIOUSLY VALIDLY TENDERED SHARES PURSUANT TO THE
OFFER AND WHO HAVE NOT WITHDRAWN THOSE SHARES NEED NOT TAKE ANY FURTHER ACTION
IN ORDER TO TENDER SHARES PURSUANT TO THE OFFER, AS AMENDED. SHAREHOLDERS WHO
HAVE TENDERED SHARES ON OR PRIOR TO SEPTEMBER 11, 1998 PURSUANT TO GUARANTEED
DELIVERY PROCEDURES SHOULD COMPLY WITH THE REQUIRED PROCEDURES. SEE SECTION 3 OF
THE OFFER TO PURCHASE.
     THIS MATERIAL IS BEING FORWARDED TO YOU AS THE BENEFICIAL OWNER OF SHARES
AND, IF APPLICABLE, RIGHTS CARRIED BY US IN YOUR ACCOUNT BUT NOT REGISTERED IN
YOUR NAME.
     A TENDER OF SUCH SHARES AND, IF APPLICABLE, RIGHTS CAN BE MADE ONLY BY US
AS THE HOLDER OF RECORD AND PURSUANT TO YOUR INSTRUCTIONS. THE LETTER OF
TRANSMITTAL IS FURNISHED TO YOU FOR YOUR INFORMATION ONLY AND CANNOT BE USED BY
YOU TO TENDER SHARES AND, IF APPLICABLE, RIGHTS HELD BY US FOR YOUR ACCOUNT.
     Accordingly, we request instructions as to whether you wish to tender any
or all of the Shares and Rights held by us for your account, upon the terms and
conditions set forth in the Offer.
     Please note the following:
          1. The Offer Price is $44.50 per Share, net to the seller in cash,
     without interest.
          2. The Offer is being made for up to an aggregate of 20,000,000 Shares
     and, if applicable, Rights. Following completion of the Offer, Offeror
     intends to promptly commence a second tender offer to purchase all
     outstanding Shares not owned by Offeror at a price of $44.50 per Share, net
     to the seller in cash, without interest thereon, upon essentially the same
     terms and conditions set forth in the Offer to Purchase.
          3. The Offer, withdrawal rights and proration period will expire at
     12:00 midnight, New York City time, on Friday, October 2, 1998, unless the
     Offer is extended.
          4. The Offer is subject to satisfaction of certain terms and
     conditions (see Introduction, Section 1 and Section 14 of the Offer to
     Purchase, Section 8 of the First Supplement and Section 7 of the Second
     Supplement).
          5. Tendering Shareholders will not be obligated to pay brokerage fees
     or commissions or, except as set forth in the Letter of Transmittal, stock
     transfer taxes on the transfer of Shares and, if applicable, Rights
     pursuant to the Offer.
          6. Payment for Shares and, if applicable, Rights accepted for payment
     pursuant to the Offer will be made only after timely receipt by The Bank of
     New York (the 'Depositary') of (i) certificates for the Shares and, if
     applicable, Rights, or timely confirmation of a book-entry transfer of the
     Shares and/or Rights into the Depositary's account at The Depository Trust
     Company (the 'Book-Entry Transfer Facility'), pursuant to the procedures
     set forth in Section 3 of the Offer to Purchase, as amended, (ii) a
     properly completed and duly executed Letter of Transmittal (or a manually
     signed facsimile) with all required signature guarantees or, in the case of
     book-entry transfer of Shares, if applicable, an Agent's Message (as
     defined in the Offer to Purchase) in connection with a book-entry transfer
     and (iii) any other documents required by the Letter of Transmittal.
     If you wish to have us tender any or all of your Shares and, if applicable,
Rights, please so instruct us by completing, executing, detaching and returning
to us the instruction form contained in this letter. An envelope to return your
instruction to us is enclosed. If you authorize tender of your Shares and, if
applicable, Rights, all such Shares and, if applicable, Rights will be tendered
unless otherwise indicated in such instruction form. PLEASE FORWARD YOUR
INSTRUCTIONS TO US AS SOON AS POSSIBLE TO ALLOW US AMPLE TIME TO TENDER YOUR
SHARES ON YOUR BEHALF PRIOR TO THE EXPIRATION OF THE OFFER.
     Offeror is not aware of any jurisdiction where the making of the Offer is
prohibited by administrative or judicial action pursuant to any valid state
statute. If Offeror becomes aware of any valid state statute prohibiting the
making of the Offer or the acceptance of the Shares or Rights pursuant thereto,
Offeror will make a good faith effort to comply with such state statute. If,
after such good faith effort, Offeror cannot comply with any such state statute,
the Offer will not be made to (nor will tenders be accepted from or on behalf
of) the holders of Shares or Rights in such state. In any jurisdiction where the
securities, blue sky or other laws require the Offer to be made by a licensed
broker or dealer, the Offer shall be deemed to be made on behalf of Offeror by
the Dealer Managers (as defined in the Offer to Purchase) or one or more
registered brokers or dealers which are licensed under the laws of such
jurisdiction.
 
                                       2

          INSTRUCTIONS WITH RESPECT TO THE OFFER TO PURCHASE FOR CASH
            UP TO AN AGGREGATE OF 20,000,000 SHARES OF COMMON STOCK
               (AND THE ASSOCIATED COMMON STOCK PURCHASE RIGHTS)
                                       OF
                                AMP INCORPORATED
 
     The undersigned acknowledge(s) receipt of your letter and the enclosed
Second Supplement, dated September 21, 1998, to the Offer to Purchase, dated
August 10, 1998, as amended by the First Supplement, dated September 14, 1998,
and the related Letter of Transmittal (which, together with any amendments or
supplements thereto, collectively constitute the 'Offer') in connection with the
offer by PMA Acquisition Corporation ('Offeror'), a Delaware corporation and a
wholly owned subsidiary of AlliedSignal Inc., a Delaware Corporation ('Parent'),
to purchase up to an aggregate of 20,000,000 shares of Common Stock, without par
value (the 'Common Stock'), and the associated Common Stock Purchase Rights (the
'Rights'), of AMP Incorporated, a Pennsylvania corporation (the 'Company'), at a
purchase price of $44.50 per Share and, if applicable, Rights, in each case net
to the seller in cash, without interest thereon, in each case upon the terms and
subject to the conditions set forth in the Offer to Purchase.
 
     This will instruct you to tender to Offeror the number of shares of Common
Stock and, if applicable, Rights, indicated below (or if no number is indicated
below, all shares of Common Stock and, if applicable, Rights) which are held by
you for the account of the undersigned, upon the terms and subject to the
conditions set forth in the Offer.
 
     Number of Shares and, if applicable, Rights to be Tendered:      Shares
 
     Unless otherwise indicated, it will be assumed that you instruct us to
tender all Shares and/or Rights held by us for your account.
 
- --------------------------------------------------------------------------------
                                   SIGN HERE
 
Signature(s)  ..................................................................
(Print Name(s))  ...............................................................
(Print Address(es))  ...........................................................
(Area Code and Telephone Number(s))  ...........................................
(Taxpayer Identification or Social Security Number(s))  ........................
- --------------------------------------------------------------------------------

                                       3

This announcement is neither an offer to purchase nor a solicitation of an offer
  to sell Shares or Rights. The Offer is made solely by the Offer to Purchase,
    dated August 10, 1998, as amended by the First Supplement thereto, dated
 September 14, 1998 and the Second Supplement thereto, dated September 21, 1998
   and the related Letters of Transmittal and is not being made to (nor will
  tenders be accepted from or on behalf of) holders of Shares or Rights in any
 jurisdiction in which the making of the Offer or the acceptance thereof would
  not be in compliance with the laws of such jurisdiction. In any jurisdiction
 where the securities, blue sky or other laws require the Offer to be made by a
licensed broker or dealer, the Offer shall be deemed to be made on behalf of the
 Purchaser by Lazard Freres & Co. LLC and Goldman, Sachs & Co. or one or more
  registered brokers or dealers licensed under the laws of such jurisdiction.
 
                          PMA ACQUISITION CORPORATION
 
                          A WHOLLY OWNED SUBSIDIARY OF
 
                               ALLIEDSIGNAL INC.
 
                                HAS AMENDED ITS
                           OFFER TO PURCHASE FOR CASH
             AND IS NOW OFFERING TO PURCHASE UP TO AN AGGREGATE OF
                       20,000,000 SHARES OF COMMON STOCK
            (INCLUDING THE ASSOCIATED COMMON STOCK PURCHASE RIGHTS)
 
                                       OF
 
                                AMP INCORPORATED
 
                                       AT
 
                              $44.50 NET PER SHARE
 
    PMA Acquisition Corporation, a Delaware corporation (the 'Purchaser'), and
a wholly owned subsidiary of AlliedSignal Inc., a Delaware corporation (the
'Parent'), is now offering to purchase up to 20,000,000 shares of common
stock, without par value (the 'Shares'), of AMP Incorporated, a Pennsylvania
corporation (the 'Company'), including the associated Common Stock Purchase
Rights (the 'Rights') issued pursuant to the Rights Agreement, dated as of
October 25, 1989, as amended, between the Company and ChaseMellon Shareholder
Services L.L.C., at a price of $44.50 per Share, net to the seller in cash
without interest thereon, upon the terms and subject to the conditions set
forth in the Offer to Purchase, dated August 10, 1998 as amended by the First
Supplement thereto, dated September 14, 1998 and the Second Supplement
thereto, dated September 21, 1998 and in the related Letters of Transmittal
(which as amended or supplemented from time to time, collectively constitute
the 'Offer'). Unless the context otherwise requires, all references herein to
Shares shall include the Rights, and all references to the Rights include the
benefits that may inure, to holders of the Rights pursuant to the Rights
Agreements referred to above, including the right to receive payment due upon
redemption of the Rights.
 
    The purpose of the Offer is to facilitate the Purchaser's acquisition of
control of, and the entire equity interest in, the Company and to obtain a
significant vote for purposes of Parent's consent solicitation pursuant to
which it is soliciting the consent of holders of Shares to certain proposals.
 
THE OFFER AND WITHDRAWAL RIGHTS EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY TIME,
            ON FRIDAY, OCTOBER 2, 1998. UNLESS THE OFFER IS EXTENDED.
 
    SHARES MAY NOT BE TENDERED PURSUANT TO GUARANTEED DELIVERY PROCEDURES
AFTER SEPTEMBER 14, 1998.
 
    SHAREHOLDERS WHO HAVE PREVIOUSLY VALIDLY TENDERED SHARES PURSUANT TO THE
OFFER AND WHO HAVE NOT WITHDRAWN THOSE SHARES NEED NOT TAKE ANY FURTHER ACTION
IN ORDER TO TENDER SHARES PURSUANT TO THE OFFER, AS AMENDED. SHAREHOLDERS WHO
HAVE TENDERED SHARES ON OR PRIOR TO SEPTEMBER 11, 1998 PURSUANT TO GUARANTEED
DELIVERY PROCEDURES SHOULD COMPLY WITH THE REQUIRED PROCEDURES. SEE SECTION 3
OF THE OFFER TO PURCHASE.

    For purposes of the Offer, the Purchaser will be deemed to have accepted for
payment, and thereby purchased, Shares validly tendered and not withdrawn, if
and when the Purchaser gives oral or written notice to The Bank of New
York (the 'Depositary') of its acceptance of the Shares for payment pursuant to
the Offer. In all cases, upon the terms and subject to the conditions of the
Offer, payment for Shares purchased pursuant to the Offer will be made by
deposit of the purchase price with the Depositary, which will act as agent
for tendering shareholders for the purpose of receiving payments from the
Purchaser and transmitting the payments to validly tendering shareholders.
Payment for Shares accepted for payment pursuant to the Offer will be made
only after timely receipt by the Depositary of (i) certificates for the Shares
or timely Book-Entry Confirmation (as defined in the Offer to Purchase) of a
book-entry transfer of the Shares into the Depositary's account at a
Book-Entry Transfer Facility (as defined in the Offer to Purchase)
and, if the Distribution Date (as defined in the Offer to Purchase)
occurs, certificates for the associated Rights or timely Book-Entry Confirmation
of such Rights, (ii) a properly completed and duly executed Letter of
Transmittal (or a manually signed facsimile) with all required signature
guarantees or an Agent's Message (as defined in the Offer to Purchase) in
connection with a book-entry transfer of Shares and (iii) any other documents
required by the Letter of Transmittal. Under no circumstances will interest on
the purchase price for Shares be paid by the Purchaser, regardless of any
extension of the Offer or any delay in making payment.
 
    Except as otherwise provided below, tenders of Shares (and, if applicable
Rights) made pursuant to the Offer are irrevocable. Shares tendered pursuant to
the Offer may be withdrawn at any time prior to the Expiration Date and, unless
therefore accepted for payment pursuant to the Offer, may also be withdrawn at
any time after October 2, 1998. Shares may not be withdrawn unless the
associated Rights are also withdrawn. For a withdrawal to be effective, a
written, telegraphic, telex or facsimile transmission notice of withdrawal must
be timely received by the Depositary at one of its addresses set forth on the
back page of the Offer to Purchase. Any notice of withdrawal must specify the
name of the person who tendered the Shares to be withdrawn, the number of Shares
to be withdrawn and the name in which the certificates representing Shares are
registered, if different from that of the person who tendered the Shares. If
certificates for Shares to be withdrawn have been delivered or otherwise
identified to the Depositary, then, prior to the physical release of these
certificates, the serial numbers on these certificates must be submitted to the
Depositary and, unless the Shares have been tendered by an Eligible Institution
(as defined in the Offer to Purchase), the signatures on the notice of
withdrawal must be guaranteed by an Eligible Institution. If Shares have been
tendered pursuant to the procedure for book-entry transfer set forth in Section
3 of the Offer to Purchase, any notice of withdrawal must also specify the name
and number of the account at the applicable Book-Entry Transfer Facility to be
credited with the withdrawn Shares, in which case a notice of withdrawal will be
effective if delivered to the Depositary by any method of delivery described in
Section 4 of the Offer to Purchase. Withdrawals of Shares may not be rescinded.
All questions as to the form and validity (including time of receipt) of notices
of withdrawal will be determined by Purchaser, in its sole discretion, and its
determination will be final and binding on all parties. None of the Purchaser,
the Depositary, the Information Agent or any other person will be under any duty
to give notification of any defects or irregularities in any notice of
withdrawal or incur any liability for failure to give any notification.

    The Second Supplement to the Offer to Purchase, a revised Letter of
Transmittal and all other relevant materials will be mailed to record holders
of Shares and will be furnished to brokers, dealers, banks, trust companies
and similar persons whose names, or the names of whose nominees, appear on
shareholders lists, or, if applicable, who are listed as participants in a
clearing agency's security position listing for subsequent transmittal to
beneficial owners of Shares by the Purchaser and by the Company.
 
    The information required to be disclosed by paragraph (e)(1)(vii) of Rule
14d-6 under the Securities Exchange Act of 1934, as amended, is contained in the
Offer to Purchase, as amended, and is incorporated herein by reference.
 
    THE OFFER TO PURCHASE, THE FIRST SUPPLEMENT, THE SECOND SUPPLEMENT AND THE
RELATED LETTERS OF TRANSMITTAL CONTAIN IMPORTANT INFORMATION WHICH SHOULD BE
READ CAREFULLY BEFORE ANY DECISION IS MADE WITH RESPECT TO THE OFFER.
 
    Questions and requests for assistance or for copies of the Offer to
Purchase, the First Supplement, the Second Supplement, the related Letters of
Transmittal and other tender offer documents may be directed to the
Information Agent or the Dealer Managers, as set forth below, and copies will be
furnished at the Purchaser's expense. Neither the Parent nor the Purchaser
will pay any fees or commissions to any broker or dealer or other person
(other than the Dealer Managers, the Depositary and the Information Agent) in
connection with the solicitation of tenders of Shares and Rights pursuant to
the Offer.
 
                      The Information Agent for the Offer is:
                              MORROW & CO., INC.
                               445 Park Avenue
                                  5th Floor
                           New York, New York 10022
                           Toll Free (800) 566-9061
                         Call Collect (212) 754-8000
 
                    Banks and Brokerage Firms Please Call:
                                (800) 662-5200
 
                    The Dealer Managers for the Offer are:
 
LAZARD FRERES & CO. LLC                     GOLDMAN SACHS & CO.
30 Rockefeller Plaza                        85 Broad Street
New York, NY 10020                          New York, New York 10004
  
September 21, 1998