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                                                                      EXHIBIT 10

                               FIFTH AMENDMENT TO
                           CREDIT AGREEMENT AND WAIVER



         THIS FIFTH AMENDMENT ("Amendment") dated as of August 11, 2003, by and
among the borrowers listed on Schedule 1 (collectively "Companies") and Comerica
Bank, a Michigan banking corporation ("Bank").

                                    RECITALS:

A.       Companies and Bank entered into a Credit Agreement dated as of April
         25, 2001 which was amended by four amendments ("Agreement").

B.       Companies and Bank desire to amend the Agreement as hereinafter set
         forth.

         NOW, THEREFORE, the parties agree as follows:

         1.       Section 9.2 of the Agreement is amended to read in its
                  entirety as follows:

                  "Permit Consolidated Tangible Net Worth at any time to be less
         than $5,650,000."

         2.       Companies violated the provisions of Section 9.2 for the
                  period ended June 30, 2003 ("Covenant Violation"). Bank hereby
                  waives any event of default arising from the Covenant
                  Violation. This waiver shall not act as a consent or waiver of
                  any other transaction, act or omission, whether related or
                  unrelated thereto, including any noncompliance with such
                  covenants for any period other than the period ended on June
                  30, 2003. This waiver shall not extend to or affect any
                  obligation, covenant, agreement or default not expressly
                  waived hereby.

         3.       Companies hereby represent and warrant that, after giving
                  effect to the amendment and waiver contained herein, (a)
                  execution, delivery and performance of this Amendment and any
                  other documents and instruments required under this Amendment
                  or the Agreement are within each Company's corporate powers,
                  have been duly authorized, are not in contravention of law or
                  the terms of any Company's Articles of Incorporation or
                  Bylaws, and do not require the consent or approval of any
                  governmental body, agency, or authority; and this Amendment
                  and any other documents and instruments required under this
                  Amendment or the Agreement, will be valid and binding in
                  accordance with their terms; (b) the continuing
                  representations and warranties of each Company set forth in
                  Sections 7.1 through 7.15 of the Agreement are true and
                  correct on and as of the date hereof with the same force and
                  effect as made on and as of the date hereof; (c) the
                  continuing representations and warranties of each Company set
                  forth in Section 7.16 of the Agreement are true and

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                  correct as of the date hereof with respect to the most recent
                  financial statements furnished to the Bank by Companies in
                  accordance with Section 8.1 of the Agreement; and (d) no Event
                  of Default (as defined in the Agreement) or condition or event
                  which, with the giving of notice or the running of time, or
                  both, would constitute an Event of Default under the
                  Agreement, as hereby amended, has occurred and is continuing
                  as of the date hereof.

         4.       Except as expressly provided herein, all of the terms and
                  conditions of the Agreement remain unchanged and in full force
                  and effect.

         5.       This Amendment shall be effective upon execution of this
                  Agreement by Companies and the Bank.

         IN WITNESS the due execution hereof as of the day and year first above
written.

COMERICA BANK                               DETREX CORPORATION



By:__________________________________       By:_________________________________
                                                  Robert M. Currie

Its:__________________________________      Its:  Secretary


                                            THE ELCO CORPORATION



                                            By:_________________________________
                                                  Robert M. Currie

                                            Its:  Secretary



                                            HARVEL PLASTICS, INC.



                                            By:_________________________________


                                            Its:________________________________



                                            S.O. REALTY, INC.



                                            By:_________________________________
                                                  Robert M. Currie

                                            Its:  Secretary

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                                   SCHEDULE 1



Detrex Corporation

The Elco Corporation

Harvel Plastics, Inc.

S.O. Realty, Inc.