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                                                                   EXHIBIT 10.29



                                                                     Parlontieri





                                December 1, 2000



Dr. Sidney E. Brown, Chairman
   of the Board of Directors
Emissions Testing, Inc.
400 Colony Park
Building 104, Suite 600
Cumming, Georgia  30041

          Re:  Letter Agreement Regarding 200,000 Shares of the Common Stock of
               Emissions Testing, Inc., a Georgia Corporation (the "Company"),
               Owned of Record by Richard A. Parlontieri ("RAP")

Dear Mr. Brown:

     As you know, RAP is the owner of record of 200,000 shares of the common
stock, no par value per share, of the Company.

     The Company has filed a registration statement on Form S-1 (the
"Registration Statement") with the Securities and Exchange Commission (the
"SEC") for the registration of certain shares of the Company's common stock
("Common Stock"), in a public offering (the "Offering") under the Securities Act
of 1933, as amended (the "Act"). Among the shares of Common Stock to be
registered in the Offering are 100,000 shares of Common Stock owned of record by
RAP ( the "Registered Shares"). The balance of the shares of Common Stock owned
by RAP, I.E., 100,000 shares, will not be registered with the SEC by the Company
in the Offering (the "Restricted Shares").

     Inasmuch as RAP wishes to induce the Company to continue its efforts in
connection with the Offering, RAP hereby agrees with, and represents to, the
Company that RAP will not, directly or indirectly, sell, offer to sell, grant an
option for the sale of, assign, transfer, pledge, hypothecate or otherwise
encumber or dispose of in any manner, any of the Registered Shares (or any
interest therein) or any of the Restricted Shares (or any interest therein),
INCLUDING, WITHOUT LIMITATION, PURSUANT TO RULE 144 OR RULE 144A UNDER THE ACT,
from and after the date hereof except as follows:

          (a)  The Company agrees that RAP shall have the right to sell, offer
               to sell, grant an option for the sale of, assign, transfer,
               pledge, hypothecate or

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Emissions Testing, Inc.
December 1, 2000
Page 2


               otherwise encumber and/or dispose of in any manner, up to and
               including 50,000 of the Registered Shares at any time after the
               moment that the SEC declares the Registration Statement effective
               under the Act (the "Effective Date"); and

          (b)  The Company further agrees that RAP shall have the right to sell,
               offer to sell, grant an option for the sale of, assign, transfer,
               pledge, hypothecate or otherwise encumber and/or dispose of in
               any manner, all or any part of the Registered Shares and all or
               any part of the Restricted Shares at any time after the earlier
               of (I) 12:01 AM (Atlanta, Georgia time) on October 1, 2001, or
               (II) the date and time that the Company has reduced to $250,000
               or below the outstanding aggregate principal amount of the
               Company's indebtedness to GCA Strategic Investment Fund Limited,
               a Bermuda corporation ("GCA") (or its assignees) under the
               convertible debentures issued and sold (before or after the date
               hereof) by the Company pursuant to the terms of that certain
               Securities Purchase Agreement dated effective as of June 1, 2000
               between the Company and GCA, as the same may be amended from time
               to time.

     RAP agrees and understands that:

          (c)  Any sale or other transaction involving all or any part of
               Registered Shares and all or any part of the Restricted Shares
               are, and shall hereafter remain, subject to all applicable
               federal and state securities laws and regulations.

          (d)  The Company may place a legend reflecting this letter and terms
               hereof on any certificate evidencing all or any part of the
               shares described herein, and may give written notice of this
               letter, and the terms hereof, to the Company's transfer agent;

          (e)  This letter, and the terms hereof, shall be binding upon RAP and
               the successors and assigns of RAP;

          (f)  The Company is relying upon the agreements and representations of
               RAP set forth in this letter in filing the Registration Statement
               and amendments thereto and in consummating the Offering; and

          (g)  If RAP receives any shares of Common Stock upon the exercise of
               any option granted to RAP by the Company ("Option Shares"), such
               Option Shares shall be subject to the terms of this Letter
               Agreement, notwithstanding any registration statement then in
               effect with respect to such Option Shares.

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Emissions Testing, Inc.
December 1, 2000
Page 3



         The Company agrees that, upon the occurrence of the event described in
subparagraph (b)(II) above, the Company shall give prompt written notice thereof
to RAP at the last known address then available to the Company.

         The parties hereto agree that this Letter Agreement shall not be
amended, modified or terminated without the prior written consent of GCA, which
consent may be granted or denied in the sole discretion of GCA.

         If the foregoing meets with your understanding of our agreement, please
so signify by signing and returning this Letter Agreement to us.

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<S>                                   <C>
                                      Very truly yours,



                                      /s/ Richard A. Parlontieri
                                      -------------------------------------
                                      Richard A. Parlontieri
</TABLE>


Agreed to and accepted as of the
day and year first above written.

EMISSIONS TESTING, INC.



By: /s/ Richard D. Downey, Director
    ---------------------------------
   Name: Richard D. Downey
        -----------------------------
   Position: Director
             ------------------------