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                                                                    EXHIBIT 4.6


                               USV PARTNERS, LLC
                         2001 PENNSYLVANIA AVENUE, N.W.
                                   SUITE 675
                             WASHINGTON, D.C. 20006
                                 (202) 466-4557

                                 March 1, 2000

U.S. Technologies Inc.
6525 The Corners Parkway
Suite 300
Norcross, Georgia 30092

Gentlemen:

         USV Partners, LLC, a Delaware limited liability company (the
"Company"), has reached this agreement with U.S. Technologies Inc., a Delaware
corporation ("US Tech"), in connection with US Tech's desire to file a
Registration Statement on Form S-8 (the "Registration Statement") under the
Securities Act of 1933, as amended, to register 3,115,000 shares of US Tech's
common stock, par value $.02 per share ("Common Stock"), to be issued by US
Tech pursuant to its 1999 Stock Option Plan, as amended (the "Plan").

         As of the date hereof, the Company owns 500,000 shares of US Tech's
Series A Convertible Preferred Stock, $0.02 par value ("Series A Preferred").
The rights and preferences of the holders of the Series A Preferred are set
forth in (i) the Certificate of Designations, Preferences and Rights of the
Series A Preferred, dated as of July 16, 1998, (ii) the Amended Certificate of
Designations, Preferences and Rights of the Series A Preferred, dated as of
February 24, 1999, and (iii) the Amended Certificate of Designations,
Preferences and Rights of the Series A Preferred, dated as of November 29, 1999
(collectively, the "Certificate of Designations"). Pursuant to the Certificate
of Designations, the shares of Series A Preferred owned by the Company are
convertible into 47,649,758 shares of Common Stock. As of the date hereof, the
Company also owns warrants to purchase 500,000 shares of Common Stock (the
"Warrants").

         The Company acknowledges that if it converted the Series A Preferred
and exercised the Warrants it owns into and for Common Stock prior to the
shares of Common Stock to be registered under the Registration Statement being
issued and delivered as contemplated by the Registration Statement and the
Plan, the number of shares of Common Stock that would be outstanding would
exceed the minimum of such shares that US Tech is authorized to issue under its
Restated Certificate of Incorporation, as amended (the "Charter"), and thus not
be validly issued.

         As a significant stockholder of US Tech, the Company has a significant
interest in US Tech's growth and development. The Company recognizes that the
ability of US Tech to issue options under the Plan will enable US Tech to
attract and retain talented employees. As a result, the Company does not desire
to impede US Tech's efforts to register the Common Stock it


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intends to issue upon the exercise of options granted under the Plan. US Tech
has agreed to seek approval for and to effect a Charter Amendment as described
below. Accordingly, notwithstanding the rights granted to US Tech under the
Certificate of Designations and the Warrants, the Company hereby makes the
following representations, warranties and covenants to US Tech:

1.       Until US Tech's voting stockholders have approved an Amendment to the
         Charter (the "Charter Amendment"), authorizing the Company to issue an
         amount of Common Stock sufficient to permit the conversion to Common
         Stock of all of US Tech's then-outstanding shares of all of its
         authorized and designated series of convertible preferred stock and
         any other then-outstanding securities and options issued by the
         Company, which are convertible into or entitle the holder thereof to
         purchase or otherwise receive shares of Common Stock, including but
         not limited to Series A Preferred, the Warrants and the options issued
         under the Plan, and the Charter Amendment has been filed with and
         accepted by the Secretary of State of the State of Delaware, the
         Company will not exercise for or convert into Common Stock the
         Warrants, the shares of the Series A Preferred Stock or any other
         securities or options held by the Company as of the date hereof that
         are convertible into or give the Company the right to purchase or
         otherwise receive shares of Common Stock.

2.       Until US Tech's voting stockholders have approved the Charter
         Amendment and it has been filed with and accepted by the Secretary of
         State of the State of Delaware, the Company will not exercise for or
         convert into Common Stock any securities and options issued by US
         Tech, which were purchased or otherwise acquired by or issued or
         granted to the Company after the date hereof and are convertible into
         or entitle the holder thereof to purchase or otherwise receive shares
         of Common Stock.

         The undersigned is authorized to act on behalf of the Company in
regard to the matters set forth in this letter.



                                  USV Partners, LLC

                                  By: USV Management, LLC, its Manager

                                  By:/s/ C. Gregory Earls
                                     --------------------
                                     C. Gregory Earls,
                                     Sole Member



Acknowledged and Agreed to
by U.S. Technologies Inc.



By:/s/ James V. Warren
   -------------------
   James V. Warren,
   Co-Chairman and Co-CEO