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                                                                      Exhibit 10

                      THIRD AMENDMENT TO CREDIT AGREEMENT


This Third Amendment to Credit Agreement (this "AMENDMENT") is made as of
February 14, 1997 by and among Lesco, Inc. ("BORROWER"), an Ohio corporation,
National City Bank, NBD Bank, and PNC Bank, National Association (the three
financial institutions hereinbefore mentioned each a "BANK" and, collectively,
the "BANKS") and National City Bank as agent (in that capacity, "NCB-AGENT") of
the banks for the purposes of the Existing Credit Agreement (as defined below),
this Amendment and the related writings:

                                  INTRODUCTION:

        WHEREAS, I. Borrower, the Banks and NCB-Agent are parties to a Credit
Agreement (the "EXISTING CREDIT AGREEMENT") made as of September 30, 1994, as
amended by a First Amendment to Credit Agreement made as of January 18, 1996,
and as further amended by a Second Amendment to Credit Agreement made as of
November 1, 1996, setting forth, among, other things, the terms and conditions
of each Bank's several agreement (its "REVOLVING COMMITMENT") to make loans
(each a "REVOLVING LOAN") to Borrower until April 30, 2000 (or such later
"Expiration Date", if any, as may be established from time to time pursuant to
the Existing Credit Agreement, subject in each case to certain terms and
conditions, one such condition being that the aggregate unpaid principal balance
of the Revolving Loans shall not at any time exceed an amount equal to eighty
million dollars ($80,000,000); and

                  II. Borrower, the Banks, and NCB-Agent desire, subject to the
terms and conditions of this Amendment, to amend the Existing Credit Agreement
in certain material respects;

       THEREFORE, in consideration of the premises, the mutual agreements herein
contained, and other valuable considerations, and in the case of the Banks and
NCB-Agent, in reliance on the representations and warranties of Borrower
hereinafter set forth, Borrower, the Banks and NCB-Agent hereby agree as
follows:

       A. DEFINED TERMS. Each term used in this Amendment that is defined in
the Existing Credit Agreement shall have the meaning in this Amendment that is
ascribed to that term in the Existing Credit Agreement.

       B. AMENDMENT TO SUBSECTION 3B. 04 - INTEREST COVERAGE. Subject to
Borrower's satisfaction of the conditions precedent set forth in paragraph E,
subsection 3D.04 (captioned "INTEREST COVERAGE") of the Existing Credit
Agreement shall be deemed to have been deleted as of December 30, 1996 (the
"RETROACTIVE EFFECTIVE DATE"), and the following, subsection 3B.04 shall be
deemed to have been inserted, as of the Retroactive Effective Date, in lieu of
the subsection so deleted:


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"3B.04 INTEREST COVERAGE -- Borrower will not, as of the end of any period (each
such period a FOUR-QUARTER PERIOD) of four consecutive quarter-annual fiscal
periods of Borrower (commencing with the Four-Quarter Period ending December 31,
1996), suffer or permit the ratio of the aggregate of

         (a) the Adjusted Net Income of the Companies for that Four-Quarter
         Period, plus

         (b) the aggregate interest expense of the Companies for that
         Four-Quarter Period, plus

         (c) the aggregate federal, state and local income taxes of the
         Companies for that Four-Quarter Period

to the aggregate interest expense of the Companies for that Four-Quarter Period
to be less than one and one-half to one (1.5:1) at any time, all as determined
on a consolidated basis. For purposes of this subsection 3B.04, the ADJUSTED NET
INCOME for any Four-Quarter Period shall be the Net Income for that Four-Quarter
Period, plus in the case of, but only in the case of, the Four-Quarter Periods
ending December 31, 1996, March 31, 1997, June 3O, 1997, September 30, 1997, and
December 31, 1997, respectively, an amount, in no case greater than ten million
five hundred thousand dollars ($10,500,000), equal to the aggregate, if and to
the extent subtracted in the computation of Net Income, of

         (i) the amount of plant relocation costs recognized by Borrower for the
         quarter-annual fiscal periods of Borrower ending December 31, 1996 and
         March 31, 1997, respectively, as a result of the relocation of
         Borrower's Sebring, Florida, manufacturing operations, plus

         (ii) the amount of the reduction in the historical cost of Borrower's
         inventory recognized by Borrower for the quarter-annual fiscal periods
         of Borrower ending December 31, 1996 and March 31, 1997,, respectively,
         as a result of Borrower's comprehensive product evaluation, plus

         (iii) the amount of the incremental valuation reserve established by
         Borrower for the quarter-annual fiscal periods of Borrower ending
         December 31, 1996 and March 31, 1997, respectively, as result of
         Borrower's review of its accounts receivable in order to evaluate the
         collectibility of amounts outstanding for more than one (1) year.

all as described in Note 9 (captioned "Other Costs and Expenses") of the
February 10, 1997 draft of Borrower's annual audit report for its fiscal year
ending December 1, 1996."

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        C. AMENDMENT TO SUBSECTION 3D.02 - CREDIT EXTENSIONS. Subject to
Borrower's satisfaction of the conditions precedent set forth in paragraph E,
subsection ')D.02 (captioned "CREDIT EXTENSIONS") of the Existing Credit
Agreement is hereby amended. as of the date of this Amendment, by deleting
the word "or" from the end of clause (iv) of that subsection, deleting the
period from the end of clause (v) of that subsection and inserting the
expression ", or" in lieu of the period so deleted, and inserting, immediately
after clause (v) of that subsection and immediately before subsection 3D.03
(captioned "BORROWINGS") of the Existing Credit Agreement the following
clause (vi)

        "(vi) any Guaranty by Borrower of the obligations of Commercial Turf
        Products, Ltd. (COMMERCIAL TURF PRODUCTS), an Ohio limited liability
        company, but only if and to the extent that Borrower's aggregate
        liability for those obligations (exclusive of Borrower's liability for
        interest, premiums, charges, expenses, and fees) under all Guaranties
        does not at any one time exceed an aggregate amount equal to twenty
        million dollars ($20,000,000)."

        D. REPRESENTATIONS AND WARRANTIES. In order to induce the Banks and
NCB-Agent to enter into this Amendment, Borrower hereby represents and warrants
to the Banks and NCB-Agent as follows:

                 (i) after giving effect to Borrower's satisfaction of the
        conditions precedent set forth in paragraph E, no Default Under This
        Agreement shall exist, nor will any thereupon begin to exist;

                 (ii) no representation, warranty, or other statement made in or
        pursuant to the Existing Credit Agreement or any Related Writing will be
        untrue or incomplete in any material respect;

                 (iii) EXHIBIT A to this Amendment sets forth a true and
        complete copy of Note 9 (captioned "Other Costs and Expenses") of the
        February 10, 1997 draft of Borrower's annual audit report for its fiscal
        year ending December 31, 1996; and

                 (iv) there has not occurred any material adverse change in
        Borrower's financial condition, properties or business since the date of
        Borrower's Most Recent 4A.04 Financial Statements or in its then most
        recent financial statements, if any, furnished to the Banks pursuant to
        subsection 3A.01 of the Existing, Credit Agreement.

The representations and warranties made in or pursuant to this paragraph D shall
survive the execution and delivery of this Amendment.

       E. Conditions Precedent. It is a condition precedent to the effectiveness
of paragraphs B and C that, on or before the date of this Amendment, Borrower
shall have complied with or caused compliance with each of the following:

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                 (i) Borrower shall have executed and delivered this Amendment
       to NCB-Agent; and

                 (ii) each Bank and NCB-Agent shall have executed and delivered
       this Amendment.

        F. EXECUTION AND DELIVERY. This Amendment may be executed in one or more
counterparts. Any party to the Existing Credit Agreement may deliver an executed
counterpart of this Amendment by transmitting a facsimile thereof to NCB-Agent
at (216) 575-9396, and any party so delivering a counterpart of this Amendment
party shall be deemed to have executed and delivered that counterpart with the
intent to be bound by this Amendment. Each party to this Amendment shall, on
NCB-Agent's request, deliver to NCB-Agent such number of counterparts bearing
the original signature of that party as NCB-Agent may request in order that each
party may ultimately have a counterpart bearing the original signature of each
party to this Amendment. Each party to this Amendment hereby assents to the
foregoing, procedure for executing and delivering this Amendment and agrees that
all such counterparts taken together shall constitute but one agreement, which
agreement constitutes the entire agreement between the parties to this Amendment
in respect of its subject matter.

        G. RATIFICATION AND CONFIRMATION. Borrower, the banks and NCB-Agent do
hereby ratify and confirm all of the terms and conditions of the Existing Credit
Agreement not specifically amended by this Amendment and all such terms and
conditions remain in full force and effect.

        IN WITNESS WHEREOF, this Amendment is executed and delivered at
Cleveland, Ohio as of the date first hereinabove set forth.

Address:                             Lesco, Inc.
 20005 Road
 Rocky River, Ohio 44116             By: /s/ Kenneth W. Didion
                                         -------------------------------

                                     Title: Treas.
                                           -----------------------------


Address:                             National City Bank, Agent
  1900 East Ninth Street
  Attn: Multinational Division       By: /s/ Timothy J. Lathe
  Cleveland, Ohio 44114-3484             -------------------------------

                                     Title: SVP
                                           -----------------------------


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Address:                             National City Bank, Agent
  1900 East Ninth Street
  Attn: Multinational Division       By: /s/ Timothy J. Lathe
  Cleveland, Ohio 44114-3484            --------------------------------

                                     Title: SVP
                                           -----------------------------

Address:                             PNC Bank, National Association
  1801 E. 9th St., #715        
  Cleveland, Ohio 44114-3103         By: /s/ David J. Williams
                                        --------------------------------

                                     Title: Vice President
                                           -----------------------------

Address:                             NBD Bank
 611 Woodward Avenue
 Detroit, Michigan 48226             By /s/ Paul R. Demelo
                                       ---------------------------------

                                     Title: V.P.
                                           -----------------------------

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