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                                                                    EXHIBIT 10.W

               AMENDMENT NO. 13 TO THE LOAN AND SECURITY AGREEMENT

         AMENDMENT NO. 13 to the Loan and Security Agreement dated as of
September 10, 2004 ("Amendment No. 13") 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, NATIONAL
ASSOCIATION, SUCCESSOR BY MERGER TO 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 amended by amendment no. 11 to the loan
and security agreement dated as of February 6, 2004, as amended by amendment no.
12 to the loan and security agreement dated as of April 29, 2004, 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. 13.

         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 "Transaction 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. 13), the term loan note by
                  Debtor in favor of Secured Party evidencing the 2003 Term
                  Loan, as the same may be extended, re-executed, modified or
                  otherwise

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                  amended from time to time, and all documents, instruments,
                  notes and agreements by 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 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 Debtor and/or Continental Systems, as the case
                  may be, to Secured Party or to create, perfect, continue the
                  perfection or protect the Secured

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                  Party's security interest in the Collateral or any of the
                  other collateral specified in the other Transaction Documents.

         2. The definition of "Termination 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) July
                  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. 13, (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. 13 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. 13 to
the Loan and Security Agreement as of the day and year first above written.

                           HSBC BANK USA, NATIONAL ASSOCIATION, SUCCESSOR BY
                           MERGER TO HSBC BANK USA, F/K/A MARINE MIDLAND BANK


                           By:  /s/ Christopher J. Mendelsohn
                                --------------------------------
                                Christopher J. Mendelsohn
                                First Vice President

                          NAPCO SECURITY SYSTEMS, INC.

                          By:        /s/Kevin Buchel
                                ------------------------
                                  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 CHRISTOPHER J. MENDELSOHN,
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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