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                                 SIXTH AMENDMENT
                                       to
                             ULTRAK OPERATING, L.P.
                   FIRST AMENDED AND RESTATED CREDIT AGREEMENT

        THIS SIXTH AMENDMENT (this "Agreement") is executed and effective as of
April 6, 2001, among ULTRAK OPERATING, L.P., a Texas limited partnership
("Borrower"), ULTRAK, INC., a Delaware corporation ("Parent"), AMERICAN NATIONAL
BANK AND TRUST COMPANY OF CHICAGO (as a "Lender"), HARRIS TRUST AND SAVINGS BANK
(as a "Lender"), and AMERICAN NATIONAL BANK AND TRUST COMPANY OF CHICAGO (as
"Administrative Agent" for present and future Lenders).

                                    RECITALS

        Borrower, Parent, Administrative Agent and Lenders are parties to that
certain First Amended and Restated Credit Agreement (as previously, hereby or
hereafter renewed, extended, modified, supplemented, amended and restated, the
"Credit Agreement") dated as of May 17, 2000, providing for, among other things,
a secured revolving credit facility. The parties to this Agreement have agreed
to amend the Credit Agreement as set forth herein.

                                   AGREEMENTS

        NOW THEREFORE, in consideration of the premises, and for other good,
fair and valuable consideration, the receipt, adequacy and reasonable
equivalency of which are hereby acknowledged, the parties hereto agree as
follows:

1.      Defined Terms; References. Unless otherwise stated in this Agreement,
terms defined in the Credit Agreement have the same meanings when used in this
Agreement. All references in the Credit Documents to the "Credit Agreement"
refer to the Credit Agreement as heretofore amended and as amended by this
Agreement. This Agreement is a "Credit Document" referred to in the Credit
Agreement, and the provisions relating to Credit Documents in the Credit
Agreement are incorporated by reference, the same as if set forth verbatim in
this Agreement.

2.      Amendments.  The Credit Agreement is hereby amended as follows:

        (a)     The following definitions are hereby added to the Credit
                Agreement:

               "First TROL Default Waiver", "Second TROL Default Waiver" and
           "Third TROL Default Waiver" means waivers by the same names granted
           pursuant to various amendments to this Credit Agreement.

               "SWBVI Advance" means the advance on or about April 6, 2001 of
           Two Million Dollars ($2,000,000) by SWBVI to Borrower, which is and
           shall be deemed to be a Permitted Intercompany Advance.




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               "SWBVI Contribution" means the contribution on or about April 6,
           2001 of Two Million One Hundred Thousand Dollars ($2,100,000) by
           Security Warranty to SWBVI.

               "SWBVI Note" means a promissory note dated April 6, 2001, in form
           and substance satisfactory to Administrative Agent, executed by
           Borrower, payable to the order of SWBVI, evidencing the indebtedness
           arising from the SWBVI Advance, which shall be pledged by SWBVI to
           Administrative Agent, for the benefit of Lenders, pursuant to a
           Security Agreement executed and delivered by SWBVI pursuant to
           Section 5.1, and possession thereof delivered to Administrative
           Agent, with an allonge endorsement satisfactory to Administrative
           Agent.

        (b)     Section 9.7(h) is amended by adding the following immediately
        before the semi-colon at the end thereof: "and the SWBVI Contribution,
        so long as, simultaneously therewith, the SWBVI Advance is made and the
        SWBVI Note is pledged to Administrative Agent pursuant to Section 5.1".

3.      Conditions Precedent. Unless one or more of the following conditions
precedent is waived by Lenders, this Agreement is effective only if, as and
when:

        (a)     Administrative Agent receives counterparts of this Agreement
        executed by Parent, Borrower, Administrative Agent, each Lender and each
        Subsidiary whose name appears on the Subsidiary Joinder at the end of
        this Agreement (each, a "Ratifying Subsidiary");

        (b)     Administrative Agent receives the original of the executed SWBVI
        Note, with a duly executed allonge endorsement acceptable to
        Administrative Agent, as a pledge by SWBVI of the SWBVI note pursuant to
        the SWBVI Security Agreement;

        (c)     Administrative Agent receives one or more certificates
        evidencing all of the issued and outstanding capital stock of SWBVI, as
        a pledge by Security Warranty of additional collateral under the Amended
        and Restated Security Agreement;

        (d)     Administrative Agent receives an Addendum to the Amended and
        Restated Security Agreement, executed by Security Warranty, confirming
        the pledge of the SWBVI capital stock to Administrative Agent;

        (e)     Administrative Agent receives a Security Agreement duly executed
        by SWBVI (the "SWBVI Security Agreement"), which will include
        subordination provisions similar to Section 10 of the Guaranty: and

        (f)     Administrative Agent receives an Amended and Restated
        Contribution and Indemnification Agreement (the "Amended Contribution
        Agreement") duly executed by Borrower and each Ratifying Subsidiary,
        amended and restating, and in substantially the same form as, the
        Contribution and Indemnification Agreement dated as of March 22, 2000
        executed by Borrower and each Ratifying Subsidiary other than SWBVI.



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4.      Certain Covenants.  Contemporaneously with the execution of this
Agreement:

        (a)     Borrower will pay in full all fees and expenses due and owing to
        Administrative Agent and each Lender, including unpaid fees and expenses
        of counsel.

        (b)     Borrower will deliver to Administrative Agent a certificate of
        (i) the Secretary of Borrower certifying as to resolutions of the board
        of directors or executive committee of Borrower authorizing and
        approving the execution of this Agreement, the SWBVI Note and the
        Amended Contribution Agreement, (ii) the Secretary of Parent certifying
        as to resolutions of the board of directors or executive committee of
        Parent authorizing and approving the execution of this Agreement, (iii)
        the Secretary of Security Warranty certifying as to resolutions of the
        board of directors or executive committee of Security Warranty
        authorizing and approving the pledge of the SWBVI stock to
        Administrative Agent and the execution of the Amended Contribution
        Agreement and (iv) the Secretary of SWBVI certifying as to (A)
        resolutions of the board of directors or executive committee of SWBVI
        authorizing and approving the SWBVI Advance, the execution of the SWBVI
        Security Agreement and the Amended Contribution Agreement and the pledge
        of the SWBVI Note to Administrative Agent and (B) the Organizational
        Documents of SWBVI attached to such certificate.

5.      Ratifications. Except as expressly modified and superseded by this
Agreement, the Credit Documents are ratified and confirmed and continue in full
force and effect. The Credit Documents, as amended by this Agreement, continue
to be legal, valid, binding and enforceable in accordance with their respective
terms. Without limiting the generality of the foregoing, Borrower and Parent,
and each Ratifying Subsidiary, hereby ratify and confirm that all Liens
heretofore granted to Administrative Agent for the benefit of Lenders were
intended to, do and continue to secure the full payment and performance of the
Obligation. Borrower and Parent agree to perform such acts and duly authorize,
execute, acknowledge, deliver, file and record such additional assignments,
security agreements, modifications or amendments to any of the foregoing, and
such other agreements, documents and instruments as Administrative Agent may
reasonably request in order to perfect and protect those Liens and preserve and
protect the Rights of Administrative Agent and Lenders in respect of all present
and future Collateral.

6.      Representations and Warranties. Borrower and Parent hereby, jointly and
severally, represent and warrant to Administrative Agent and Lenders that (a)
this Agreement and any other Credit Documents to be delivered under this
Agreement have been duly executed and delivered by or on behalf of Borrower and
each other Company party to them, are valid and binding upon Borrower and the
other Companies and are enforceable against Borrower and the other Companies in
accordance with their respective terms, except as limited by any applicable
Debtor Relief Laws, (b) no action of, or filing with, any Governmental Authority
is required to authorize, or is otherwise required in connection with, the
execution, delivery and performance by Borrower or any other Company of this
Agreement or any other Credit Document to be delivered under this Agreement, (c)
the execution, delivery and performance by Borrower and the other Companies of
this Agreement and any other Credit Documents to be delivered under this
Agreement do not require the consent of any other Person and do not and will not
constitute a violation of any Laws, agreements or understandings to which
Borrower or any other Company is a party or by which Borrower or any other
Company is bound, (d) the representations and warranties contained in the Credit
Agreement, as amended by this Agreement, and any other Credit Documents are true
and correct in all material respects as of the date of this Agreement, (e) no
Event of Default or Potential Default exists, other than the Events of Default
and Potential Defaults to which the First TROL Default Waiver, Second TROL
Default Waiver and Third TROL Default Waiver relate, and (f) each Company has
performed all of its obligations under the Credit Agreement and other Credit
Documents.



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7.      Counterparts.  This Agreement may be executed in any number of
counterparts with the same effect as if all signatories had signed the same
document.

8.      Parties Bound. This Agreement binds and inures to the benefit of
Borrower, Lenders and Administrative Agent and, subject to Section 14.12 of the
Credit Agreement, their respective successors and assigns.

9.      ENTIRETY. THIS AGREEMENT, THE CREDIT AGREEMENT AS AMENDED BY THIS
AGREEMENT, AND THE OTHER CREDIT DOCUMENTS REPRESENT THE FINAL AGREEMENT BETWEEN
THE PARTIES FOR THE TRANSACTIONS HEREIN AND THEREIN, AND MAY NOT BE CONTRADICTED
BY EVIDENCE OF PRIOR, CONTEMPORANEOUS, OR SUBSEQUENT ORAL AGREEMENT BETWEEN THE
PARTIES. THERE ARE NO UNWRITTEN ORAL AGREEMENTS BETWEEN THE PARTIES.

        EXECUTED AND EFFECTIVE as of April 6, 2001.

               ULTRAK, INC., as Parent

               By:    /s/ Chris T. Sharng
                  ------------------------------------------------------
                      Chris T. Sharng, Senior Vice President and Chief Financial
                      Officer

               ULTRAK OPERATING, L.P. as Borrower
               By: Ultrak GP, Inc. its General Partner

               By:    /s/ Chris T. Sharng
                  ------------------------------------------------------
                      Chris T. Sharng, Senior Vice President and Chief Financial
                      Officer

               AMERICAN NATIONAL BANK AND TRUST COMPANY OF CHICAGO
                      as Administrative Agent and a Lender

               By:    /s/ Donna H. Evans
                  ------------------------------------------------------
                      Donna H. Evans, Vice President

               HARRIS TRUST AND SAVINGS BANK, as a Lender

               By:    /s/ William Robin
                  ------------------------------------------------------
                      William Robin, Vice President



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                               SUBSIDIARY JOINDER

        To induce Administrative Agent and Lenders to enter into this Agreement,
each Subsidiary named below (a) consents and agrees to this Agreement's
execution and delivery, (b) ratifies and confirms that all guaranties,
assurances and Liens granted, conveyed or assigned to Administrative Agent for
the benefit of Lenders under the Credit Documents are not released, diminished,
impaired, reduced or otherwise adversely affected by this or any prior
amendment, and continue to guarantee, assure and secure the full payment and
performance of the Obligation, (c) agrees to perform such acts and duly
authorize, execute, acknowledge, deliver, file and record such additional
guaranties, assignments, security agreements, deeds of trust, mortgages and
other agreements, documents, instruments and certificates as Administrative
Agent may reasonably deem necessary or appropriate in order to create, perfect,
preserve and protect those guaranties, assurances and Liens, and (d) waives
notice of acceptance of this consent and agreement, which consent and agreement
binds each of the undersigned and their respective successors and permitted
assigns and inures to the benefit of Administrative Agent and Lenders and their
respective successors and permitted assigns.

               ULTRAK GP, INC.

               By:    /s/ Chris. T. Sharng
                   -----------------------------------------------------
                      Chris T. Sharng, Senior Vice President and Chief Financial
                      Officer

               ULTRAK, LP, INC.

               By:    /s/ Chris T. Sharng
                   -----------------------------------------------------
                      Chris T. Sharng, Senior Vice President and Chief Financial
                      Officer

               DIAMOND ELECTRONICS, INC.

               By:    /s/ Chris T. Sharng
                  ------------------------------------------------------
                      Chris T. Sharng, Senior Vice President and Chief Financial
                      Officer

               MONITOR DYNAMICS, INC.

               By:    /s/ Chris T. Sharng
                  ------------------------------------------------------
                      Chris T. Sharng, Senior Vice President and Chief Financial
                      Officer

               ABM DATA SYSTEMS, INC.

               By:    /s/ Chris T. Sharng
                  ------------------------------------------------------
                      Chris T. Sharng, Senior Vice President and Chief Financial
                      Officer

               SECURITY WARRANTY, INC.

               By:    /s/ Chris T. Sharng
                  -----------------------------------------------------
                      Chris T. Sharng, Senior Vice President and Chief Financial
                      Officer

               SECURITY WARRANTY (BVI) LTD.

               By:    /s/ Chris T. Sharng
                   ----------------------------------------------------
                      Chris T. Sharng, Director


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