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                                                                EXHIBIT 10.12(a)


                               SEVENTH AMENDMENT
                         DATED AS OF DECEMBER 26, 2003
                                       TO
                           RECEIVABLES SALE AGREEMENT
                          DATED AS OF DECEMBER 21,2001

         THIS SEVENTH AMENDMENT (the "Amendment"), dated as of December 26,
2003, is entered into among PerkinElmer Receivables Company, as Seller (the
"Seller"), PerkinElmer, Inc., as Initial Collection Agent (the "Initial
Collection Agent," and together with any successor thereto, the "Collection
Agents"), the committed purchasers party thereto (the "Committed Purchasers"),
Windmill Funding Corporation ("Windmill"), and ABN AMRO Bank N.V., as agent for
the Purchasers (the "Agent")

                                  WITNESSETH:

         WHEREAS, the Seller, the Initial Collection Agent, the Agent, the
Committed Purchasers and Windmill have heretofore executed and delivered a
Receivables Sale Agreement, dated as of December 21, 2001 (as amended,
supplemented or otherwise modified through the date hereof, the "Sale
Agreement"),

         WHEREAS, the parties hereto desire to amend the Sale Agreement as
provided herein;

         NOW, THEREFORE, for good and valuable consideration, the receipt and
adequacy of which are hereby acknowledged, the parties hereto hereby agree that
the Sale Agreement shall be and is hereby amended as follows:

         Section 1. The defined term "Credit Agreement" appearing in Schedule I
to the Sale Agreement is hereby amended in its entirety and as so amended shall
read as follows:

                     "Credit Agreement" means that certain $415,000,000 Credit
               Agreement dated as of December 26, 2002, as amended by Amendment
               No. 3 to Credit Agreement dated as of December 26, 2003
               ("Amendment No. 3"), among the Parent, the lenders from time to
               time party thereto, Merrill Lynch & Co., Merrill Lynch, Pierce,
               Fenner and Smith Incorporated, as arranger, Merrill Lynch Capital
               Corporation, as syndication agent and Bank of America, N.A., as
               administrative agent, and all amendments prior to Amendment No.
               3.

         Section 2. This Amendment shall become effective on the date the Agent
has received (i) counterparts hereof executed by Seller, Initial Collection
Agent, each Purchaser and the Agent and (ii) an executed Guarantor's
Acknowledgment and Consent.

         Section 3. To induce the Agent and the Purchasers to enter into this
Amendment, the Seller and Initial Collection Agent represent and warrant to the
Agent and the Purchasers that: (a) the representations and warranties contained
in the Transaction Documents, are true and

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correct in all material respects as of the date hereof with the same effect as
though made on the date hereof (it being understood and agreed that any
representation or warranty which by its terms is made as of a specified date
shall be required to be true and correct in all material respects only as of
such specified date); (b) no Potential Termination Event exists; (c) this
Amendment has been duly authorized by all necessary corporate proceedings and
duly executed and delivered by each of the Seller and the Initial Collection
Agent, and the Sale Agreement, as amended by this Amendment, and each of the
other Transaction Documents are the legal, valid and binding obligations of the
Seller and the Initial Collection Agent, enforceable against the Seller and the
Initial Collection Agent in accordance with their respective terms, except as
enforceability may be limited by bankruptcy, insolvency or other similar laws of
general application affecting the enforcement of creditors' rights or by general
principles of equity; and (d) no consent, approval, authorization, order,
registration or qualification with any governmental authority is required for,
and in the absence of which would adversely effect, the legal and valid
execution and delivery or performance by the Seller or the Initial Collection
Agent of this Amendment or the performance by the Seller or the Initial
Collection Agent of the Sale Agreement, as amended by this Amendment, or any
other Transaction Document to which they are a party.

         Section 4. This Amendment may be executed in any number of counterparts
and by the different parties on separate counterparts and each such counterpart
shall be deemed to be an original, but all such counterparts shall together
constitute but one and the same Amendment.

         Section 5. Except as specifically provided above, the Sale Agreement
and the other Transaction Documents shall remain in full force and effect and
are hereby ratified and confirmed in all respects. Nothing herein shall be
interpreted as permitting any Lien to be granted to any Person in the
Receivables or any other property of the Originators or the Seller in which the
Agent or any Purchaser has an interest under the Transaction Documents. The
execution, delivery, and effectiveness of this Amendment shall not operate as a
waiver of any right, power, or remedy of any Agent or any Purchaser under the
Sale Agreement or any of the other Transaction Documents, nor constitute a
waiver or modification of any provision of any of the other Transaction
Documents. All defined terms used herein and not defined herein shall have the
same meaning herein as in the Sale Agreement. The Seller agrees to pay on demand
all costs and expenses (including reasonable fees and expenses of counsel) of or
incurred by the Agent and each Purchaser Agent in connection with the
negotiation, preparation, execution and delivery of this Amendment.

         Section 6. This Amendment and the rights and obligations of the parties
hereunder shall be construed in accordance with and be governed by the law of
the State of Illinois.

                                       -2-

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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 Committed Purchaser

                                           By: /s/ Patricia Luken
                                               ---------------------------------
                                           Title: Group Vice President

                                           By: /s/ Kevin G. Pilz
                                               ---------------------------------
                                           Title: Kevin G. Pilz
                                                  Vice President

                                           WINDMILL FUNDING CORPORATION

                                           By: /s/ [ILLEGIBLE]
                                               ---------------------------------
                                           Title: Vice President

                                           PERKINELMER RECEIVABLES COMPANY

                                           By:/s/ John L. Healy
                                              ----------------------------------
                                           Title: John L. Healy,
                                                  Vice President & Secretary

                                           PERKINELMER, INC.

                                           By:/s/ John L. Healy
                                              ----------------------------------
                                           Title: John L. Healy, Assistant Clerk

                                      -3-

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                     GUARANTOR'S ACKNOWLEDGMENT AND CONSENT

         The undersigned, PerkinElmer, Inc., has heretofore executed and
delivered the Limited Guaranty dated as of December 21, 2001 (the "Guaranty")
and hereby consents to the Amendment to the Sale Agreement as set forth above
and confirms that the Guaranty and all of the undersigned's obligations
thereunder remain in full force and effect. The undersigned further agrees that
the consent of the undersigned to any further amendments to the Sale Agreement
shall not be required as a result of this consent having been obtained, except
to the extent, if any, required by the Guaranty referred to above.

                                           PERKINELMER, INC.

                                           By:/s/ Robert F. Friel
                                              ----------------------------------
                                           Title: Robert F. Friel, SVP & CFO