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                                                                   EXHIBIT 10.12

                               FIRST AMENDMENT TO
                         FIREARMS TRAINING SYSTEMS, INC.
                             STOCK OPTION AGREEMENT
                                    SERIES A


                  WHEREAS, Firearms Training Systems, Inc., a Delaware
corporation (the "Company"), has heretofore granted to the optionee named below
(the "Optionee") a non-qualified option to purchase from the Company shares of
its Class A Common Stock upon and subject to the terms and conditions of a Stock
Option Agreement, Series A dated September 18, 1996 (the "Agreement"); and
                  WHEREAS, the Company and the Optionee desire to amend the
Agreement in certain respects;

                  NOW, THEREFORE, the Agreement is amended effective as of June
26, 1998 in the following respects:

         1.       Section 2.2(a) of the Agreement is amended by deleting the
words "and with respect to an additional sixteen and two-thirds percent
(16-2/3%) of the shares of Stock subject to the Option if such termination
occurs after the second anniversary of the Option Date.", and by adding two new
sentences at the end thereof to read as follows:

         Notwithstanding the foregoing, if the Optionee's active employment
         ceases in accordance with the Confidential Resignation Agreement (as
         hereinafter defined), then (i) the Optionee's employment shall be
         deemed to have terminated on January 1, 1999 for purposes of this
         paragraph, (ii) such termination shall be deemed to be a termination by
         the Company other than for Cause (as defined herein), provided the
         terms and conditions of the Confidential Resignation Agreement are
         complied with and (iii) subject to Section 2.5 below, the Option shall
         become exercisable with respect to 45,000 of the remaining shares of
         Stock subject to the Option (the "Transition Shares") at the end of the
         Compliance Period (as defined in the Confidential Resignation
         Agreement). For purposes of this Agreement, "Confidential Resignation
         Agreement" means the


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         resignation agreement between the Company and the Optionee dated June
         26, 1998.

         2.       Section 2.2(e) of the Agreement is amended in its entirety to
read as follows:

                  (e) If the Optionee terminates employment with the Company for
         any reason other than as described in subsection (b), (c) or (d) above,
         the Option shall be exercisable only to the extent it is exercisable on
         the effective date of the Optionee's termination of employment (except
         for the Transition Shares, which shall remain exercisable as set forth
         in this Agreement) and may thereafter be exercised by the Optionee or
         the Optionee's Legal Representative until and including the latest to
         occur of (i) the date that is 90 days after the effective date of the
         Optionee's termination of employment (ii) the date on which the
         Optionee is determined to be noncompliant with Paragraph 16 thereof,
         and (iii) if no violation of Paragraph 16 of the Confidential
         Resignation Agreement occurs during the Compliance Period, the date
         that is twelve months after the end of the Compliance Period; provided
         that if the Optionee's employment is terminated by the Company for
         Cause at any time, the Option shall terminate automatically on the
         effective date of the Optionee's termination of employment, and the
         Optionee shall be subject to the provisions of Section 2.5.

         3.       Section 2.5 of the Agreement is amended in the following
respects:
         (i) to insert the phrase "In the event of a determination of the
Optionee's noncompliance with the Confidential Resignation Agreement on account
of the Optionee's breach or failure to comply with his obligations thereunder as
described in Paragraph 16 thereof, or" at the beginning of subsection (a)
thereof,
         (ii) to insert the phrase "the date of such determination of
noncompliance or" before the phrase "the date the Optionee engages in such
activity" as it appears twice in subsection (a) thereof, and before the phrase
"the

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date on which the Optionee engaged in such activity" as it appears in
subsection (a) thereof, and
         (iii) to add the parenthetical phrase "(or in the case of a breach of
the Confidential Resignation Agreement, the Chief Executive Officer)" after the
word "Committee" as it appears in subsection (b) thereof.

         4. Section 3.5 of the Agreement is amended in the following respects:

         (i) by adding at line four of Section 3.5, after the words "Section 3.8
of the Plan", the phrase "which results in a sale by the Centre Entities (as
described in the Prospectus for Firearms Training Systems, Inc. dated November
26, 1996) of all or substantially all of the assets of the Company or the shares
held by the Centre Entities (a "Qualifying Change in Control")", and to replace
the words "Change in Control" with "Qualifying Change in Control" throughout
Section 3.5 thereafter,
         (ii) to substitute the phrase "there shall be substituted for each
share of Stock for which this Option is exercisable as of the date of the
Qualifying Change in Control" for the phrase "all outstanding options shall
immediately be exercisable in full and there shall be substituted for each share
of Stock available under this Plan, whether or not then subject to an
outstanding option," as it appears in the first sentence of the first paragraph
thereof,
         (iii) to substitute the phrase "the Option" for the phrase "each
option" as it appears in the second sentence of the first paragraph thereof,
         (iv) to add the phrase "for which the Option is exercisable as of the
date of occurrence of such Qualifying Change in Control" after the phrase "a
cash payment from the Company in an amount equal to the number of shares of
Stock 


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then subject to such option" as it appears in the second paragraph
thereof, and
         (v) to add a new paragraph at the end thereof to read as follows:

                  In the event of a Qualifying Change in Control prior to the
         end of the Compliance Period, the portion of the Option which is
         attributable to the Transition Shares shall be deemed to be exercisable
         for purposes of this Section 3.5

         This instrument may be executed in two counterparts, each of which
shall be deemed an original and both of which together shall constitute one and
the same instrument.


                                            FIREARMS TRAINING SYSTEMS, INC.




                                            By:/s/ Peter A. Marino
                                               -------------------
                                               Peter A. Marino
                                               President


Accepted this 26th day of June, 1998.



/s/ Robert B. Terry, Jr.
------------------------
Robert B. Terry, Jr.