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                                                                    EXHIBIT 10.U

               AMENDMENT NO. 11 TO THE LOAN AND SECURITY AGREEMENT

         AMENDMENT NO. 11 to the Loan and Security Agreement dated as of
February 6, 2004 ("Amendment No. 11") by and between NAPCO SECURITY SYSTEMS,
INC., a New York corporation having a place of business at 333 Bayview Avenue,
Amityville, New York 11701 (the "Debtor") and HSBC BANK USA F/K/A MARINE MIDLAND
BANK, having a place of business at 534 Broad Hollow Road, Melville, New York
11747 (the "Secured Party").

                              W I T N E S S E T H :

         WHEREAS, as of May 12, 1997, Debtor and Secured Party had entered into
a certain loan and security agreement, as amended by amendment no. 1 to the loan
and security agreement dated as of May 28, 1998, as amended by amendment no. 2
to the loan and security agreement dated as of June 30, 1999, as amended by
amendment no. 3 to the loan and security agreement dated as of February 9, 2000,
as amended by amendment no.4 to the loan and security agreement dated as of July
27, 2000, as amended by amendment no. 5 to the loan and security agreement dated
as of September 22, 2000, as amended by amendment no. 6 to the loan and security
agreement dated as of November 22, 2000, as amended by amendment no. 7 to the
loan and security agreement dated as of February 14, 2001, as amended by
amendment no. 8 to the loan and security agreement dated as of May 15, 2001, as
amended by amendment no. 9 to the loan and security agreement dated as of
September 30, 2001, as amended by amendment no. 10 to the loan and security
agreement dated as of March 13, 2003, as may be amended from time to time (the
"Agreement");

         WHEREAS, the Debtor has requested that Secured Party extend the
Termination Date and the Secured Party has agreed to do so, in the manner set
forth below, provided however, that, among other things, Debtor execute this
Amendment No. 11.

         NOW, THEREFORE, in consideration of the mutual promises and for other
good and valuable consideration, the receipt of which is hereby acknowledged,
the parties hereto agree as follows:

         1. The definition of ATransaction Documents@ contained in Section 1.1.
of the Agreement is hereby amended to read in its entirety as follows:

                  TRANSACTION DOCUMENTS means, individually, jointly, severally
                  and collectively, the Agreement (including all amendments to
                  date, including this Amendment No. 11), the term loan note
                  dated as of even date hereof by Debtor in favor of Secured
                  Party evidencing the 2003 Term Loan, as the same may be
                  extended, re-executed, modified or otherwise amended from time
                  to time, and all documents, instruments, notes and agreements
                  by

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                  Debtor, Continental Systems or any other Third Party or any
                  Responsible Party in favor of Secured Party, whether in
                  existence now or hereinafter created, executed and delivered
                  to Secured Party, as the same may be extended, re-executed,
                  modified or otherwise amended from time to time, including,
                  without limitation, the Term Loan Note, the Continental Term
                  Loan Note, the Note, collateral documents, letter of credit
                  agreements, notes, acceptance credit agreements, security
                  agreements, pledges, guaranties, mortgages, title insurance,
                  assignments, and subordination agreements required to be
                  executed by Debtor, Continental Systems any other Third Party,
                  or any Responsible Party pursuant hereto or in connection
                  herewith, or in connection with a letter of credit application
                  and reimbursement agreement, each dated as of May 12, 1997, as
                  may be reaffirmed or restated from time to time, a certain
                  uncommitted trade line established by Secured Party in favor
                  of Debtor to provide for commercial and standby letters of
                  credit, evidenced by, among other documents, a continuing
                  letter of credit agreement, and a continuing indemnity
                  agreement, each dated as of May 12, 1997, as may be
                  re-executed, amended, extended or otherwise modified from time
                  to time, the Term Loan Note in the principal sum of
                  $2,500,000.00, as may be extended or otherwise modified from
                  time to time, the Note, the Continental Term Loan Note in the
                  principal sum of $8,250,000, that certain ISDA master
                  agreement dated as of July 27, 2000 by and between Continental
                  Systems and Secured Party, inclusive of all schedules thereto,
                  as the same may be modified from time to time (the AMaster
                  Agreement@) and all such other mortgages, security agreements,
                  guaranties and other documents as may be executed and
                  delivered to Secured Party to evidence, guaranty and secure
                  the Continental Term Loan Note, and the obligations
                  thereunder, as may be extended or otherwise modified from time
                  to time, and uncommitted line of credit facility to be used by
                  Debtor to finance certain acquisitions, as may be executed and
                  delivered to Secured Party from time to time to evidence and
                  secure the obligations under such facilities pursuant to the
                  terms that the Secured Party shall request, and all other
                  documents, agreements, reaffirmations, certificates and
                  resolutions related thereto, and amendments or supplements
                  thereto, all such other agreements, resolutions, certificates,
                  resolutions and opinion letters executed and/or issued as a
                  condition precedent to or in connection with the Agreement,
                  the Term Loan Note, Note, the Continental Term Loan Note, and
                  all such other documents, agreements, and instruments
                  delivered hereunder or as a supplement or amendment thereto or
                  as Secured Party may reasonably require from time to time in
                  order to evidence, guaranty and/or secure any and all
                  indebtedness of

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                  Debtor and/or Continental Systems, as the case may be, to
                  Secured Party or to create, perfect, continue the perfection
                  or protect the Secured Party's security interest in the
                  Collateral or any of the other collateral specified in the
                  other Transaction Documents.

         2. The definition of ATermination Date@ contained in Section 1.1. of
the Agreement is hereby amended to read in its entirety as follows:

                  TERMINATION DATE shall mean the earlier to occur of (a)
                  January 15, 2005, or, if such day shall not be a Business Day,
                  the next succeeding Business Day, or (b) upon the occurrence
                  of an Event of Default.

         3. As an inducement to the Bank extending the Revolving Credit Facility
and the Agreement pursuant to the terms hereof, Debtor represents and warrants
to Secured Party that, as of the date of execution of this Amendment No. 11, (i)
the representations and warranties set forth in Article 4 of the Agreement and
the representations and warranties of Debtor and any Third Party set forth in
the other Transaction Documents to which any is a party are true and correct in
all respects, (ii) no event has occurred and is continuing which constitutes an
"Event of Default" under any of the Transaction Documents (as "Event of Default"
is defined in each of those Transaction Documents"), (iii) Debtor is in
compliance with the covenants set forth in Articles 9 and 10 of the Agreement,
as modified herein; and(iv) Debtor will pay Secured Party=s reasonable legal
fees and disbursements thereof.

         4. Debtor represents and warrants to Secured Party that there are no
offsets, defenses or counterclaims to the payment of the Indebtedness owing
Secured Party, including the Advances, and to the continuing general security
interest in the Collateral granted to Secured Party by Debtor as security for
payment of the Indebtedness, as fully described in the Agreement.

         5. Except as modified herein, all other provisions of the Agreement and
the other Transaction Documents remain unmodified and are in full force and
effect.

         6. Capitalized terms not otherwise defined herein shall have the
meanings ascribed to such terms in the Agreement.

         7. This Amendment No. 11 shall be governed by the laws of the State of
New York.

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         IN WITNESS WHEREOF, the parties have executed this Amendment No. 11 to
the Loan and Security Agreement as of the day and year first above written.

                                      HSBC BANK USA F/K/A MARINE MIDLAND BANK

                                      By:                                 ,
                                               --------------------------
                                               Roger Coleman
                                               Vice President


                                      NAPCO SECURITY SYSTEMS, INC.

                                      By:                                ,
                                               --------------------------
                                                Kevin Buchel
                                                Senior Vice President

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STATE OF NEW YORK )
                           ) SS:
COUNTY OF ____      )

On this ____ day of ___________, 2004, before me, the undersigned, a Notary
Public in and for said State, personally came ROGER COLEMAN, personally known to
me or proved to me on the basis of satisfactory evidence to be the person, whose
name is subscribed to the within instrument and acknowledged to me that he
executed the same in his capacity and that by his signature on the instrument,
the person or entity upon behalf of which the person acted executed the
instrument.

                              ________________________________  Notary Public

STATE OF NEW YORK      )
                                ) SS:
COUNTY OF __________)

On this ____ day of ________, 2004, before me, the undersigned, a Notary Public
in and for said State, personally came KEVIN BUCHEL personally known to me or
proved to me on the basis of satisfactory evidence to be the person, whose name
is subscribed to the within instrument and acknowledged to me that he executed
the same in his capacity and that by his signature on the instrument, the person
or entity upon behalf of which the person acted executed the instrument.

                             _______________________________    Notary Public



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