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                                                                    Exhibit 10.4



                              ASSUMPTION AGREEMENT


         This ASSUMPTION AGREEMENT (this "Agreement"), dated as of May 2, 2000,
is executed and delivered by INTERLOGIX, INC., a Delaware corporation (formerly
known as ITI TECHNOLOGIES, INC.) ("INTERLOGIX") and PNC BANK, NATIONAL
ASSOCIATION, as administrative agent (the "Administrative Agent") for the
Lenders (defined below).

                                   WITNESSETH:

         WHEREAS, pursuant to a Credit Agreement, dated as of November 17, 1999
(as amended, supplemented, amended and restated or otherwise modified from time
to time, the "Credit Agreement") among SLC Technologies, INC., a Delaware
corporation (the "Borrower") , the various financial institutions as are, or may
from time to time become, parties thereto (collectively, the "Lenders"), and the
Administrative Agent for the Lenders, the Lenders have extended Commitments
(such capitalized term and the other terms used herein to have the meanings
provided in Article I below) to make Credit Extensions to the Borrower on or
after the Merger Date;

         WHEREAS, upon consummation of the Merger, INTERLOGIX is required to
assume each and every obligation of the Borrower under the Credit Agreement,
each other Loan Document and each other document and agreement entered into in
connection therewith, and to execute and deliver this Agreement; and

         WHEREAS, INTERLOGIX has duly authorized the execution, delivery and
performance of this Agreement;

         NOW THEREFORE, for good and valuable consideration, the receipt of
which is hereby acknowledged by INTERLOGIX, and to induce the Lenders to make
Credit Extensions to INTERLOGIX pursuant to the Credit Agreement, INTERLOGIX
agrees with the Administrative Agent for the benefit of all the Lenders as
follows:

                                   ARTICLE I
                                   DEFINITIONS

         Section 1.1. Certain Terms. The following terms (whether or not
underscored) when used in this Agreement, including its preamble and recitals,
shall have the following meanings (such definitions to be equally applicable to
the singular and plural forms thereof)

         "Administrative Agent" is defined in the preamble.

         "Agreement" is defined in the preamble.

         "Borrower" is defined in the first recital.
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         "Credit Agreement" is defined in the first recital.

         "Lenders" is defined in the first recital.

         Section 1.2. Credit Agreement Definitions. Unless otherwise defined
herein or the context otherwise requires, terms for which meanings are provided
in the Credit Agreement are used in this Agreement, and its preamble and
recitals, with such meanings.

                                   ARTICLE II
                                   ASSUMPTION

         Section 2.1. Assumption of Obligations. Effective as of the Merger
Effective Time, INTERLOGIX, as the successor in interest to the Borrower, hereby

              (a) assumes (by operation of law and pursuant to this Agreement)
         and agrees to be bound by, perform, observe, and hereby confirms each
         and every covenant, agreement, term, condition, obligation,
         appointment, duty and liability of the Borrower under and with respect
         to the Credit Agreement, each other Loan Document and each other
         document and agreement entered into in connection therewith;

              (b) accepts and assumes all liabilities of the Borrower related to
         any representation or warranty made by, and all rights and powers of
         the Borrower under or in connection with, the Credit Agreement, each
         other Loan Document and each other document and agreement entered into
         in connection therewith, and confirms and restates all such
         representations and warranties;

              (c) confirms and acknowledges that it is the "Borrower" referred
         to in the Credit Agreement, each other Loan Document and each other
         document and agreement entered into in connection therewith that was
         executed and delivered by the Borrower, and hereby agrees to perform
         and observe all the covenants, agreements, terms, conditions,
         obligations, appointments, duties and liabilities of the Borrower under
         the Credit Agreement, each other Loan Document and each other document
         and agreement entered into in connection therewith that was executed
         and delivered by the Borrower, as if it had been the "Borrower"
         thereunder from the original execution and delivery thereof;

              (d) confirms and agrees that it possesses all the rights,
         privileges, powers and franchises (both public and private), and is
         subject to all the restrictions, disabilities and duties of the
         Borrower, and that the rights of the Lenders under the Credit Agreement
         and each other Loan Document shall be unimpaired and remain in full
         force and effect and are hereby ratified and confirmed in all respects;
         and

              (e) confirms and acknowledges that (i) INTERLOGIX is a corporation
         duly incorporated and validly existing in good standing under the laws
         of the State of Delaware, (ii) the Borrower had (A) all requisite power
         and authority to enter into the Merger and to authorize the assumption
         of the rights and obligations in connection therewith and (B) duly
         authorized the Merger and the assumption of rights and obligations in
         connection therewith, (iii) the consummation of the Merger and the

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         assumption by INTERLOGIX of all the rights and obligations of the
         Borrower will not violate or result in a default under any applicable
         laws, rules or regulations or material agreements (except as set forth
         in the Credit Agreement), orders or judgments binding on or applicable
         to the Borrower, and (v) the Credit Agreement, each other Loan Document
         and each other document and agreement entered into in connection
         therewith is in full force and effect and binding and enforceable
         against INTERLOGIX in accordance with their applicable terms (in each
         case, subject to the effects of bankruptcy, insolvency, fraudulent
         conveyance, reorganization, moratorium and other similar laws relating
         to or affecting creditors' rights generally, general equitable
         principles (whether considered in a proceeding in equity or at law) and
         an implied covenant of good faith and fair dealing).

                                  ARTICLE III
                                 MISCELLANEOUS

         Section 3.1. Further Assurances. Without limitation to the other terms
and provisions of this Agreement, INTERLOGIX agrees to execute and deliver, from
time to time, such documents or agreements as the Administrative Agent may
reasonably request to give effect to the terms of this Agreement.

         Section 3.2. Loan Document. This Agreement is a Loan Document executed
pursuant to the Credit Agreement, and shall be administered, construed and
applied in accordance with the terms and provisions thereof, including Article X
thereof.

         Section 3.3. Successors and Assigns; Benefits. This Agreement shall be
binding upon INTERLOGIX and its successors and assigns and shall inure to the
benefit of each of the Lenders, the Administrative Agent and each of their
respective successors and assigns.

         Section 3.4. Counterparts. This Agreement may be executed in any number
of counterparts, each of which shall be an original and all of which when taken
together shall constitute one and the same agreement.

         Section 3.5. Governing Law. THIS AGREEMENT SHALL BE GOVERNED BY AND
CONSTRUED IN ACCORDANCE WITH THE INTERNAL LAWS OF THE STATE OF NEW YORK.

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         IN WITNESS WHEREOF, each of the undersigned has caused this Agreement
to be executed by its duly authorized officer as of the date and year first
above written.

                                       INTERLOGIX, INC.

                                       By
                                         ---------------------------------------
                                            Name:
                                            Title:





                                       PNC BANK, NATIONAL ASSOCIATION,
                                           as Administrative Agent

                                       By
                                         ---------------------------------------
                                            Name:
                                            Title:










                             [ASSUMPTION AGREEMENT]
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         IN WITNESS WHEREOF, each of the undersigned has caused this Agreement
to be executed by its duly authorized officer as of the date and year first
above written.


                                       INTERLOGIX, INC.

                                       By /s/ Kenneth L. Boyda
                                          --------------------
                                           Name:   Kenneth L. Boyda
                                           Title:  President & CEO





                                       PNC BANK, NATIONAL ASSOCIATION,
                                          as Administrative Agent

                                       By /s/ Amy T. Petersen
                                          -------------------
                                           Name:     Amy T. Petersen
                                           Title:    Vice President