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                                                                   Exhibit 10.21

   SECOND AMENDMENT TO REVOLVING CREDIT, EQUIPMENT LOAN AND SECURITY AGREEMENT

THIS Second Amendment to Revolving Credit, Equipment Loan and Security Agreement
(this "Amendment") amends that certain Revolving Credit, Equipment Loan and
Security Agreement dated as of August 6, 2003 (the "Agreement") between TRANSACT
TECHNOLOGIES INCORPORATED (the "Borrower"), and Banknorth N.A., a national
banking association (the "Bank") as amended by a First Amendment to Revolving
Credit, Equipment Loan and Security Agreement dated November 12, 2004 (the
"First Amendment") (collectively, the Agreement, the First Amendment and this
Amendment and any further or other amendment shall be referred to as the "Credit
Agreement") is made and entered into as of the 31st day of December 2005 by and
between the Borrower and the Bank. Capitalized terms used herein but not defined
shall have the meanings assigned to them in the Credit Agreement.

1.   AMENDMENT TO CREDIT AGREEMENT. In consideration of mutual covenants herein
     contained and for other good and valuable consideration, the receipt and
     sufficiency of which are hereby acknowledged, the Borrower and the Bank do
     hereby amend the Credit Agreement as follows:

     a.   Section 7.1 of the Credit Agreement is amended in its entirety to read
          as follows:

     7.1 Operating Cash Flow to Total Debt Service Ratio. Borrower shall,
     maintain a ratio of Operating Cash Flow plus the applicable Permitted Add
     Back as provided below to Total Debt Service at the end of each fiscal
     quarter of not less than 1.25 to 1.00.

<TABLE>
<CAPTION>
     Period Ending                                   Permitted Add Back
     -------------                                   ------------------
<S>                                                  <C>
     Fiscal Year Ending December 31, 2005            not to exceed $1,500,000
     Fiscal Quarter Ending March 31, 2006            not to exceed $1,500,000
     Fiscal Quarter Ending June 30, 2006             not to exceed $1,000,000
     All Fiscal Quarters Ending after June 30, 2006  $0.00
</TABLE>

     b.   Exhibit 1 is amended by adding the following definitions in their
          entirety:

     "Permitted Add Back" means an amount of Capital Expenditures incurred
     during the fiscal year of the Borrower ending December 31, 2005 by the
     Borrower that can be characterized as financed Capital Expenditures for
     purposes of calculating the covenant


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     set forth in Section 7.1, but only in the amounts and for the fiscal
     periods provided for in Section 7.1 of this Agreement.

2.   CONDITIONS TO CLOSING. This Amendment shall be effective as of December 31,
     2005 upon the completion of each of the following:

     a.   Execution of this Amendment by the Borrower and the Bank and delivery
          of executed originals to the Bank.

     b.   Update to any Schedules to the Credit Agreement not previously
          provided to the Bank by the Borrower.

     c.   Such additional documents, certificates and other assurances that Bank
          or its counsel may require.

3.   NO DEFAULT; REPRESENTATIONS AND WARRANTIES, ETC. The Borrower hereby
     confirms that: (a) the representations and warranties of the Borrower
     contained in the Credit Agreement as modified hereby are true on and as of
     the date hereof as if made on such date (except to the extent that such
     representations and warranties expressly relate to an earlier date), as
     modified by any amendment of Schedules presented herewith; (b) the Borrower
     is in compliance in all material respects with all of the terms and
     provisions set forth in the Credit Agreement on their part to be observed
     or performed; and (c) after giving effect to this Amendment, no Event of
     Default, nor any event which with the giving of notice or expiration of any
     applicable grace period or both would constitute such an Event of Default,
     shall have occurred and be continuing.

4.   MISCELLANEOUS.

     a.   Except to the extent specifically amended hereby, the Credit
          Agreement, the Loan Documents and all related documents shall remain
          in full force and effect. Whenever the terms or sections amended
          hereby shall be referred to in the Credit Agreement, Loan Documents or
          such other documents (whether directly or by incorporation into other
          defined terms), such defined terms shall be deemed to refer to those
          terms or sections as amended by this Amendment.

     b.   This Amendment may be executed in any number of counterparts, each of
          which, when executed and delivered, shall be an original, but all
          counterparts shall together constitute one instrument.

     c.   This Amendment shall be governed by the laws of the State of
          Connecticut and shall be binding upon and inure to the benefit of the
          parties hereto and their respective successors and assigns.

                          [SIGNATURES ON THE NEXT PAGE]


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     IN WITNESS WHEREOF, the parties hereto have executed this Amendment which
is a sealed instrument as of the date first above written.

                                        BANKNORTH, N.A.


                                        By: /s/ James Hickson
                                            ------------------------------------
                                            James Hickson
                                        It's Vice President


                                        TRANSACT TECHNOLOGIES INCORPORATED.


                                        By: /s/ Steven A. DeMartino
                                            ------------------------------------
                                        Name: Steven A. DeMartino
                                        Title: Executive Vice President and
                                               Chief Financial Officer


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