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                                   Exhibit 4.
                                   ----------

                           THIRD AMENDMENT AGREEMENT

        THIRD AMENDMENT AGREEMENT (this "Amendment"), dated as of July 31,
1996, among BELL INDUSTRIES, INC., a California corporation (together with its
successors and assigns, the "Company"), and each of the holders of Notes (as
such term is defined below) whose name appears on the signature pages hereof
(individually, a "Holder" and, collectively, the "Holders").


                                   RECITALS:

        WHEREAS, the Company entered into separate Note Purchase Agreements
(collectively, as amended to, but excluding, the date hereof, the "Existing
Note Purchase Agreement," and the Existing Note Purchase Agreement, as amended
by this Amendment, the "Amended Note Purchase Agreement") with each of the
original purchasers of the Company's issuance of Fifty Million Dollars
($50,000,000) or 9.70% Senior Notes due February 1, 2001 (the "Notes");

        WHEREAS, each of the Holders is a holder of the Notes;

        WHEREAS, the Company has requested the Holders to agree to the amendment
of certain financial covenants thereunder; and

        WHEREAS, the Holders are agreeable to such amendments, on the terms and
conditions hereinafter set forth;

        NOW, THEREFORE, in consideration of the premises and other valuable
consideration, the receipt and sufficiency of which are hereby acknowledged,
the parties agree as follows:

SECTION 1.      DEFINITIONS

        Capitalized terms used in this Amendment and not otherwise defined
herein shall have the respective meanings ascribed to them in the Existing Note
Purchase Agreement.

SECTION 2.      AMENDMENTS

        2.1.    Section 7.6(c) of the Existing Note Purchase Agreement is hereby
amended and restated in its entirety as follows:

                (c)   REVOLVING CREDIT AGREEMENT.  The Company agrees to use its
        best efforts to maintain the Union Revolving Credit Agreement (or any
        substantially equivalent agreement or agreements substituted therefor or
        in addition thereto with one or more Acceptable Banks).  The Company
        agrees not to have owing to any single Acceptable Bank at any one time
        Revolving Credit Loans or other similar Debt in excess of Twenty-Five
        Million Dollars ($25,000,000), provided that, in any case, Revolving
        Credit Loans or other similar Debt owing to Union Bank and outstanding
        under the Union Revolving Credit Agreement may exceed, in the aggregate,
        Twenty-Five Million Dollars ($25,000,000) but shall not, in any case,
        exceed, in the aggregate, One Hundred Million Dollars ($100,000,000).

                
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        2.2     Section 7.7 of the Existing Note Purchase Agreement is hereby
amended and restated in its entirety as follows:

        7.7     FIXED CHARGE COVERAGE.

                The Company will not at any time permit Consolidated Net
        Operating Earnings Available for Fixed Charges, determined in respect of
        the period of four (4) consecutive fiscal quarters of the Company then
        most recently ended, to be less than two hundred fifty percent (250%) of
        Consolidated Fixed Charges, determined in respect of such period.

SECTION 3.      REPRESENTATIONS AND WARRANTIES.

        The Company represents and warrants to each of the Holders as follows:

        3.1     The Company:

                (a)     is a corporation duly organized and validly existing in
        good standing under the laws of the State of California;

                (b)     has all requisite power and authority and all necessary
        licenses and permits to own and operate its Properties and to carry on
        its business as now conducted and presently proposed to be conducted;
        and

                (c)     is duly qualified and is authorized to do business and
        is in good standing as a foreign corporation in each jurisdiction where
        the character of its Properties or the nature of its activities makes
        such qualification necessary.

        3.2     The Company has the corporate power and authority to authorize,
execute, deliver and enter into this Amendment and to perform its obligations
under the Amended Note Purchase Agreement, the Collateral Trust Indenture, the
Security Agreement, the Notes and the Warrants.

        3.3     This Amendment has been duly authorized, executed and delivered
by the Company. The Amended Note Purchase Agreement, the Collateral Trust
Indenture, the Security Agreement, the Notes and the Warrants constitute the
legal, valid and binding obligations of the Company, enforceable in accordance
with their respective terms, except that the enforceability of this Agreement
or thereof may be:

                (a)     limited by bankruptcy, insolvency or other similar laws
        affecting the enforceability of creditors' rights generally; and

                (b)     subject to the availability of equitable remedies.

The holders of the Notes are entitled to the benefits of the Amended Note
Purchase Agreement and the holders of the Warrants are entitled to the benefits
of the Warrant Agreement.

        3.4     The authorization, execution and delivery by the Company of
this Amendment is not, and the performance by the Company of its obligations
under the Amended Note Purchase Agreement will not be, inconsistent with its
certificate of incorporation or by-laws, does not and 


                                       
BELL INDUSTRIES, INC.                  2             THIRD AMENDMENT AGREEMENT
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will not contravene any law, governmental rule or regulation, judgment or order
applicable to the Company, and does not and will not contravene any provision
of, or constitute a default under, any indenture, mortgage, contract or other
instrument to which the Company is a party or by which any of its Property is
bound.

        3.5.    No consent or approval of, giving of notice to, registration
with, or taking of any other action in respect of or by, any federal, state or
local governmental authority or agency, or other Person is required with respect
to the execution and delivery by the Company of this Amendment and the
performance by the Company of any of its obligations under the Amended Note
Purchase Agreement, the Collateral Trust Indenture, the Security Agreement, the
Notes and the Warrants.

        3.6.    After giving effect to this Amendment, no Default or Event of
Default will exist.

SECTION 4.      COSTS AND EXPENSES.

        The Company shall pay all fees and expenses of Hebb & Gitlin in
connection with the negotiation, preparation and execution of this Amendment
promptly upon receipt of a statement therefor.

SECTION 5.      MISCELLANEOUS.

        5.1.    This Amendment shall become effective upon the execution and
delivery hereof by the Company and the Majority Holders.

        5.2.    This Amendment may be executed in one or more counterparts, all
of which taken together shall constitute a single instrument.

        5.3.    THIS AMENDMENT SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE
WITH, THE LAWS OF THE STATE OF CONNECTICUT.

        5.4.    Except as expressly provided herein (a) no other terms and
provisions of the Existing Note Purchase Agreement shall be modified or changed
by this Amendment and (b) the terms and provisions of the Existing Note Purchase
Agreement, as amended by this Amendment, shall continue in full force and
effect.  The Company hereby acknowledges and reaffirms all of its obligations
and duties under the Existing Note Purchase Agreement as modified by this
Amendment and under the Notes issued thereunder.

        5.5.    All headings and captions preceding the text of the several
paragraphs of this Amendment are intended solely for convenience of reference
and shall not constitute a part of this Amendment nor shall they affect it
meaning, construction or effect.

     [Remainder of page intentionally blank.  Next page is signature page.]





BELL INDUSTRIES, INC.                  3               THIRD AMENDMENT AGREEMENT
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        IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
duly executed by their respective authorized officers as of the day and year
first above written.


                                       BELL INDUSTRIES, INC.


                                       By  /s/  BRUCE M. JAFFE
                                         ---------------------------------
                                         Name:  Bruce M. Jaffe
                                         Title: President and Chief
                                                Operating Officer 

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                                       CIG & CO.

                                       By  /s/  JAMES R. KUZEMCHAK
                                         ---------------------------------
                                         Name:  James R. Kuzemchak
                                         Title: Partner

                                       THE NORTHWESTERN MUTUAL LIFE
                                       INSURANCE COMPANY

                                       By  /s/  GARY A. POLINER
                                         ---------------------------------
                                         Name:  Gary A. Poliner
                                         Title: Vice President

                                       ROYAL MACCABEES LIFE INSURANCE COMPANY
                                      
                                       By  /s/  LEONARD D. DAVENPORT
                                         ---------------------------------
                                         Name:  Leonard D. Davenport
                                         Title: Vice President
                                                Royal Investment Management
                                                Company

                                       PROVIDENT MUTUAL LIFE INSURANCE
                                       COMPANY OF PHILADELPHIA

                                       By  /s/  J.C. LANGE
                                         ---------------------------------
                                         Name:  J.C. Lange
                                         Title: Vice President

                                       PAN-AMERICAN LIFE INSURANCE
                                       COMPANY

                                       By  /s/  F. ANDERSON STONE
                                         ---------------------------------
                                         Name:  F. Anderson Stone
                                         Title: Vice President
                                                Corporate Securities

                                       SOUTHERN FARM BUREAU LIFE
                                       INSURANCE COMPANY

                                       By
                                         ---------------------------------
                                         Name:  
                                         Title: 
                                       
                                       THE UNION CENTRAL LIFE INSURANCE
                                       COMPANY

                                       By  /s/  GARY R. RODMAKER
                                         ---------------------------------
                                         Name:  Gary R. Rodmaker
                                         Title: Second Vice President

                                       UNITED COMPANIES LIFE INSURANCE
                                       COMPANY

                                       By  /s/  R. ANDREW DAVIDSON
                                         ---------------------------------
                                         Name:  R. Andrew Davidson
                                         Title: Senior Vice President

                                       WASHINGTON NATIONAL INSURANCE
                                       COMPANY

                                       By  /s/  C. BRUCE DUNN
                                         ---------------------------------
                                         Name:  C. Bruce Dunn
                                         Title: Director of Investments

                                       NATIONAL LIFE INSURANCE COMPANY

                                       By  /s/  R. SCOTT HIGGINS
                                         ---------------------------------
                                         Name:  R. Scott Higgins
                                         Title: Vice President - NLIMC