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                                                                    Exhibit 10.3

                                 FIRST AMENDMENT
                         DATED AS OF SEPTEMBER 29, 2000
                                       TO
                           RECEIVABLES SALE AGREEMENT
                           DATED AS OF OCTOBER 1, 1999

         THIS AMENDMENT (the "Amendment"), dated as of September 29, 2000, is
entered into among Ametek Receivables Corp. (the "Seller"), Ametek, Inc. (the
"Initial Collection Agent"), Amsterdam Funding Corporation, a Delaware
corporation ("Amsterdam"), ABN AMRO Bank N.V., as Amsterdam's program letter of
credit provider (the "Enhancer"), the Liquidity Provider listed on the signature
page hereof (the "Liquidity Provider") and ABN AMRO Bank N.V., as agent for
Amsterdam, the Enhancer and the Liquidity Provider (the "Agent").

         Reference is hereby made to that certain Receivables Sale Agreement,
dated as of October 1, 1999 (as amended, supplemented or otherwise modified
through the date hereof, the "Sale Agreement"), among the Seller, the Initial
Collection Agent, Amsterdam, the Enhancer, the Liquidity Provider and the Agent.
Terms used herein and not otherwise defined herein which are defined in the Sale
Agreement or the other Transaction Documents (as defined in the Sale Agreement)
shall have the same meaning herein as defined therein.

         For good and valuable consideration, the receipt and adequacy of which
are hereby acknowledged, the parties hereto hereby agree as follows:

         Section 1. Subject to the following terms and conditions, including
without limitation the conditions precedent set forth in Section 2, upon
execution by the parties hereto in the space provided for that purpose below,
the Sale Agreement shall be, and it hereby is, amended as follows:

                  (a) The date "September 29, 2000" appearing in clause (d) of
         the defined term "Liquidity Termination Date" appearing in Schedule I
         of the Sale Agreement is deleted and replaced with the date "October
         31, 2000".

                  (b) The date "September 29, 2000" appearing in clause (c)(ii)
         of the defined term "Termination Date" appearing in Schedule I of the
         Sale Agreement is deleted and replaced with the date "October 31,
         2000".

         Section 2. Section 1 of this Agreement shall become effective only once
the Agent has received, in form and substance satisfactory to the Agent, all
documents and certificates as the Agent may reasonably request and all other
matters incident to the execution hereof are satisfactory to the Agent.

         Section 3. The Sale Agreement, as amended and supplemented hereby or as
contemplated herein, and all rights and powers created thereby and thereunder or
under the other Transaction Documents and all other documents executed in
connection therewith, are in all respects ratified and confirmed. From and after
the date hereof, the Sale Agreement shall be
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amended and supplemented as herein provided, and, except as so amended and
supplemented, the Sale Agreement, each of the other Transaction Documents and
all other documents executed in connection therewith shall remain in full force
and effect.

         Section 4. This Amendment may be executed in two or more counterparts,
each of which shall constitute an original but both or all of which, when taken
together, shall constitute but one instrument.

         Section 5. This Amendment shall be governed and construed in accordance
with the internal laws of the State of New York.






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         IN WITNESS WHEREOF, the parties have caused this Amendment to be
executed and delivered by their duly authorized officers as of the date first
above written.

                                      ABN AMRO BANK N.V., as the Agent, as the
                                        Liquidity Provider and as the Enhancer



                                      By:  /s/ Thomas J. Educate
                                         ---------------------------
                                      Title:  Group Vice President
                                            ------------------------------



                                      By:  /s/ W. Robert Poff
                                         ---------------------------
                                      Title:  Group Vice President
                                            ------------------------------


                                      AMSTERDAM FUNDING CORPORATION



                                      By:   /s/ Andrew Stidd
                                         ---------------------------
                                      Title:  President
                                            ------------------------------

                                      AMETEK RECEIVABLES CORP., as Seller



                                      By:  /s/ Deirdre D. Saunders
                                         ---------------------------
                                      Title:  Vice President and Treasurer
                                            ------------------------------

                                      AMETEK, INC., as Initial Collection Agent



                                      By:  /s/ Deirdre D. Saunders
                                         ---------------------------
                                      Title:  Vice President and Treasurer
                                            ------------------------------




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