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                                                                   Exhibit 10.42

                                  [LETTERHEAD]

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                                     December 17, 1999

VIA FEDERAL EXPRESS

Mr. James J. Cramer
Cramer Partners, L.P.
40 Fulton Street, 24th fl.
New York, NY  10038

Dear Mr. Cramer:

     The purpose of this letter is to set forth our agreement with respect to
the purchase by UFP Technologies, Inc. ("UFP") of 570,000 shares of the common
stock (the "Common Stock") of UFP from the persons listed on Schedule A hereto
(the "Cramers").

     1. Subject to the approval of UFP's Board of Directors, UFP hereby agrees
to purchase 570,000 shares of Common Stock (the "Stock") from the Cramers
pursuant to the terms hereof at $2-13/16 per share. Upon notice of satisfaction
of the conditions set forth in this Section 1, the Cramers shall deliver
promptly to UFP certificates representing the Stock, endorsed in blank and in
proper form for transfer (the "Certificates"). Upon receipt of the Certificates,
UFP shall wire the purchase price for the Stock in accordance with the written
instructions of James J. Cramer.

     2. The Cramers hereby represent and warrant that: (i) the Cramers own, hold
and have good and marketable title to all the Stock, free and clear of any and
all liens, pledges and encumbrances of any kind, (ii) the Cramers have
beneficially owned the Stock for more than two years prior to the date of this
Agreement, (iii) the Cramers are authorized to enter into this Agreement and the
transactions contemplated hereby and (iv) the Cramers' execution of this
Agreement and performance of the Cramers' obligations under this Agreement will
not violate, breach or conflict with any agreements or court orders to which the
Cramers are subject.

     3. The Cramers hereby further acknowledge: (i) that the Cramers approached
UFP and proposed that UFP repurchase the Stock; (ii) that UFP from time to time
considers strategic alliances, joint ventures and acquisitions, as well as share
buy-back, going-private and change-of-control transactions; and (iii) that there
may be material, nonpublic information regarding UFP that has not been disclosed
to the Cramers and that could dramatically increase or decrease the value of the
Stock, such as information

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James J. Cramer
Cramer Partners, L.P.
December 17, 1999, page 2
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concerning transactions like those described above or other matters, such as
product introductions, new customers or changes in the competitive landscape.

     4. The Cramers hereby acknowledge and agree that the Cramers will not,
directly or indirectly, without the prior written consent of UFP, sell, offer,
contract to sell, pledge, grant any option to purchase or otherwise dispose of
any shares of Common Stock (other than the Stock in accordance with the
provisions of this Agreement) or any securities convertible into or exchangeable
for, or any rights to purchase or acquire, Common Stock held by them or which
may be deemed to be beneficially owned by them pursuant to the rules and
regulations promulgated under the Securities Act of 1933, as amended, for a
period of 180 days after the date of this Agreement. The foregoing sentence
shall not apply: (a) to transfers by way of testate or intestate cessation or by
operational law; (b) to transfers to members of the immediate family of the
undersigned who agree in writing to be bound by the terms and provisions of this
paragraph 4 or to a trust, partnership, limited liability company or any other
entity, all of the beneficial interests of which are held by the undersigned;
(c) to transfers to charitable organizations who agree in writing to be bound by
the terms and provisions of this paragraph 4; (d) to transactions relating to
shares of Common Stock or other securities acquired in open market transactions
after the completion of the sale of the Stock back to UFP as contemplated by
this Agreement; or (e) to transfers pursuant to any tender offer, exchange
offer, merger or other extraordinary transaction which is recommended by the
Board of Directors of UFP.

     5. The Cramers, on their behalf and on behalf of each of their affiliates,
hereby release and forever discharge UFP, and each of UFP's respective past,
present and future representatives, affiliates, stockholders, directors,
officers, controlling persons, subsidiaries, successors and assigns
(individually, a "Releasee" and collectively, "Releasees") from any and all
claims, demands, proceedings, causes of action, orders, obligations, contracts,
agreements, debts and liabilities whatsoever, whether known or unknown,
suspected or unsuspected, both at law and in equity, which the Cramers or any of
the Cramers' respective affiliates now have, have ever had or may hereafter have
against the respective Releasees arising by virtue of the sale of Stock
hereunder.

     6. This Agreement constitutes the entire agreement between the parties. No
amendment of any provision of this Agreement shall be valid unless the same
shall be in writing and signed by all of the parties. No waiver by any party of
any default, misrepresentation or breach of warranty or a covenant hereunder,
whether intentional or not, shall be effective unless in writing and signed by a
person duly authorized to waive the interests of such party. No such waiver
shall be deemed to extend to any prior or subsequent default, misrepresentation
or breach of warranty or covenant hereunder or affect in any way any rights
arising by virtue of any prior or subsequent such occurrence. This Agreement may
be executed in multiple counterparts, each of which shall be deemed an original
but all of which together shall constitute one and the same instrument. This

<PAGE>

James J. Cramer
Cramer Partners, L.P.
December 17, 1999, page 3
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Agreement shall be governed by and construed in accordance with the laws of The
Commonwealth of Massachusetts, regardless of the laws that might otherwise
govern under applicable conflicts of laws thereof.

     If the agreement set forth herein is acceptable to you, please sign below
where indicated.

                                       Sincerely,
                                       UFP TECHNOLOGIES, INC.

                                       By: /s/ R. JEFFREY BAILLY
                                          ------------------------------------
                                          R. Jeffrey Bailly, President & CEO

Accepted and Agreed:
J.J. CRAMER & CO.

By:
    ----------------------------

 /s/ JAMES J. CRAMER
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James J. Cramer


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Karen L. Cramer


CRAMER PARTNERS, L.P.
By:   CRAMER CAPITAL CORPORATION
      Its general partner

By:  /s/ JAMES J. CRAMER
    ----------------------------
     Name:  James J. Cramer
     Title: President

CRAMER CAPITAL CORPORATION

By:  /s/ JAMES J. CRAMER
    ----------------------------
     Name:  James J. Cramer
     Title: President


<PAGE>

James J. Cramer
Cramer Partners, L.P.
December 17, 1999, page 4
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                                   SCHEDULE A

                                J.J. Cramer & CO.
                                 James J. Cramer
                                 Karen L. Cramer
                              Cramer Partners, L.P.
                           Cramer Capital Corporation