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                                                               EXHIBIT 10.12 (c)
                                 THIRD AMENDMENT
                          DATED AS OF DECEMBER 20,2002
                                       TO
                           RECEIVABLES SALE AGREEMENT
                          DATED AS OF DECEMBER 21,2001

         This THIRD AMENDMENT (the "Amendment"), dated as of December 20, 2002,
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 "Liquidity Termination Date"
appearing in Schedule I to the Sale Agreement is hereby amended by deleting the
date "December 20, 2002 " appearing in clause (d) thereof and inserting in its
place the date "January 31, 2003".

         Section 2.        The defined term "Termination Event" appearing in
Schedule I to the Sale Agreement is hereby amended by (i) deleting "or " at the
end of clause (k) and adding "; " in lieu thereof, (ii) by adding "or" at the
end of clause (1) and (iii) adding a new clause at the end thereof as follows:

                           (m) if any Originator grants a lien on any of its
                  inventory to any Persons, failure by all of such Persons (or
                  their authorized representative) to enter into an
                  intercreditor agreement with the Agent in form and substance
                  satisfactory to the Agent.

         Section 3.        This Amendment shall become effective on the date the
Agent (i) has received counterparts hereof executed by the Seller, Initial
Collection Agent, each Purchaser and the Agent and (ii) has received executed
counterparts of the Second Amendment to Fee Letter.

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         Section 4.1.      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 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 4.2.      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 4.3.      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 4.4.      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:    GVP
                                             -----------------------------------

                                       By:  /s/ Nancy C. Buhe
                                            ------------------------------------
                                       Title:    GVP
                                             -----------------------------------

                                       WINDMILL FUNDING CORPORATION

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

                                       PERKINELMER RECEIVABLES COMPANY

                                       By: /s/ David C. Francisco
                                           -------------------------------------
                                       Title: Assistant Treasurer

                                       PERKINELMER, INC.

                                       By: /s/ Robert F. Friel
                                           -------------------------------------
                                       Title: Senior Vice President and Chief
                                              Financial Officer

                                      -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: Senior Vice President and Chief
                                              Financial Officer