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                                                                    EXHIBIT 4-12

                                    AGREEMENT
                         (10-1/2% Senior Unsecured Note)

         This Agreement dated as of January 31, 2000 (the "Agreement"), between
Lexington Precision Corporation, a Delaware corporation (the "Company"), and
Tri-Links Investment Trust, a Delaware trust (as successor-in-trust to Nomura
Holding America, Inc.) ("Tri-Links").

         WHEREAS, Tri-Links is the holder of that certain 10-1/2% Senior
Unsecured Note due February 1, 2000, of the Company in the original principal
amount of the U.S. $7,500,000, dated October 27, 1997, No. SU-1 (the "Original
Note");

         NOW, THEREFORE, in consideration of the mutual covenants contained
herein and for other good and valuable consideration, the receipt and adequacy
of which are hereby acknowledged, the parties hereto intending to be legally
bound, hereby agree as follows:

         1. Waiver.

                  Subject to paragraph 2, hereof, Tri-Links hereby waives, until
May 1, 2000, any Event of Default under the Original Note resulting solely from
the failure of the Company to pay any principal or interest due on February 1,
2000 in respect of (a) the Company's 14% Junior Subordinated Notes due May 1,
2000, (b) the Company's Junior Subordinated Convertible Increasing Rate Notes
due May 1, 2000, and/or (c) the Company's 12-3/4% Senior Subordinated Notes due
February 1, 2000 (the indebtedness referred to in clauses (a), (b) and (c) is
referred to herein as the "Other Indebtedness").

         2. Rescission of Waivers.

                  The foregoing waivers shall be automatically rescinded,
without notice to the Company, in the event that the holder of any Other
Indebtedness or trustee in respect thereof seeks to accelerate the maturity of
any such Other Indebtedness or to enforce or exercise any remedies in respect
thereto.

         3. Effective Date.

                  This Agreement shall be deemed effective as of January 31,
2000.

         4. Representations and Warranties. Each of the parties represents and
warrants that: (a) the execution, delivery and performance of this Agreement
have been duly authorized by all requisite action on its part; and (b) this
Agreement has been duly executed and delivered by it and constitutes its legal,
valid, and binding agreement, enforceable against it in accordance with its
terms, except as such enforceability may be limited by applicable bankruptcy,
insolvency, reorganization, moratorium, or similar laws affecting the
enforceability of creditors' rights generally or general equitable principles.

         5. No Other Agreements.

                  Except as expressly amended, waived, modified, and
supplemented hereby, the Original Note shall remain in full force and effect in
accordance with its terms.
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         6. General Provisions.

                  (a) Defined Terms. Capitalized terms used herein, unless
otherwise defined herein, shall have the meaning ascribed thereto in the
Original Note.

                  (b) Counterparts. This Agreement may be executed by the
parties in any number of counterparts and all of said counterparts taken
together shall be deemed to constitute one and the same instrument. This
Agreement may be signed by facsimile transmission of the relevant signature
pages hereof.

                  (c) Governing Law. This Agreement shall be governed by, and
construed and interpreted in accordance with, the internal laws of the State of
New York.

                  (d) Successors and Assigns. This Agreement shall be binding
upon and inure to the benefit of the successors and assigns of the parties
hereto and any and all transferees and holders of the Original Note or any other
Note.

                  (e) Headings. The paragraph headings of this Agreement are for
convenience of reference only and are not to be considered in construing this
Agreement.
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                  IN WITNESS WHEREOF, the Company and Tri-Links have caused this
Agreement to be duly executed and delivered by their respective proper and duly
authorized officers effective as of the first date written above.

                                   LEXINGTON PRECISION CORPORATION



                                   By:  /s/ Warren Delano
                                   Name:    Warren Delano
                                   Title:   President



                                   TRI-LINKS INVESTMENT TRUST by
                                   Wilmington Trust Company as Owner Trustee



                                   By:  /s/ David A. Vanaskey, Jr.
                                   Name:    David A. Vanaskey, Jr.
                                   Title:   Vice President



                                     CONSENT

         The undersigned, Lexington Rubber Group, Inc. (formerly Lexington
Components, Inc.), a Delaware corporation, hereby consents to the foregoing
Agreement (the "Agreement") dated as of of January 31, 2000, and effective as of
January 31, 2000, between Lexington Precision Corporation (the "Company") and
Tri-Links Investment Trust (as successor-in-interest to Nomura Holding America,
Inc., with respect to the Company's 10% Senior Unsecured Notes due February 1,
2000 (as amended, the "Original Notes"), and hereby confirms and agrees that its
Guarantee of the Original Notes shall continue to be in full force and effect
and shall apply to the Original Notes as modified by the Agreement.

                                   LEXINGTON RUBBER GROUP, INC.



                                   By:  /s/ Warren Delano
                                   Name:    Warren Delano
                                   Title:   President

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