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                                                                     Exhibit 4.3


NO. WB                         VOID AFTER , 2006                        WARRANTS
                     CLASS B REDEEMABLE WARRANT CERTIFICATE
                   UNITY EMERGING TECHNOLOGY VENTURE ONE LTD.

THIS CERTIFIES THAT, FOR VALUE RECEIVED                                    CUSIP


or registered assigns (the "Registered Holder") is the owner of the number of
Class B Redeemable Warrants (the "Warrants") specified above. Each Warrant
initially entitles the Registered Holder to purchase, subject to the terms and
conditions set forth in this Certificate and the Warrant Agreement (as
hereinafter defined), one fully paid and nonassessable share of Common Stock,
$.0001 par value, of Unity Emerging Technology Venture One Ltd., a Delaware
corporation (the "Company"), at any time from the Commencement Date (as
hereinafter defined) to the Expiration Date (as hereinafter defined) upon the
presentation and surrender of this Warrant Certificate with the Subscription
Form on the reverse hereof duly executed, at the corporate office of American
Stock Transfer & Trust Company, 40 Wall Street, New York, New York 10005, as
Warrant Agent, or its successor (the "Warrant Agent"), accompanied by payment of
$7.50, subject to adjustment (the "Purchase Price"), in lawful money of the
United States of America in cash or by check made payable to the Warrant Agent
for the account of the Company.

      This Warrant Certificate and each Warrant represented hereby are issued
pursuant to and are subject in all respects to the terms and conditions set
forth in the Warrant Agreement (the "Warrant Agreement"), dated as of , 2000, by
and between the Company and the Warrant Agent.

      In the event of certain contingencies provided for in the Warrant
Agreement, the Purchase Price and the number of shares of Common Stock subject
to purchase upon the exercise of each Warrant represented hereby are subject to
modification or adjustment.

      Each Warrant represented hereby is exercisable at the option of the
Registered Holder, but no fractional interests will be issued. In the case of
the exercise of less than all the Warrants represented hereby, the Company shall
cancel this Warrant Certificate upon the surrender hereof and shall execute and
deliver a new Warrant Certificate or Warrant Certificates of like tenor, which
the Warrant Agent shall countersign, for the balance of such Warrants.

      The term "Commencement Date" shall mean the later of (i) , 2001 or (ii)
the date of the consummation of a merger, exchange of capital stock, asset
acquisition or other similar business combination of the Company with an
operating business. The term "Expiration Date" shall mean 5:00 P.M. (New York
City time) on , 2006. If each such date shall in the State of New York be a
holiday or a day on which the banks are authorized to close, then such date
shall mean 5:00 P.M. (New York City time) the next following day which in the
State of New York is not a holiday or a day on which banks are authorized to
close.

      The Company shall not be obligated to deliver any securities pursuant to
the exercise of this Warrant unless a registration statement under the
Securities Act of 1933, as amended (the "Act"), with respect to such securities
is effective or an exemption thereunder is available. The Company has covenanted
and agreed that it will file a registration statement under the Federal
securities laws, use its best efforts to cause the same to become effective, to
keep such registration statement current, if required under the Act, while any
of the Warrants are outstanding, and deliver a prospectus which complies with
Section 10(a)(3) of the Act to the Registered Holder exercising this Warrant.


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      This Warrant shall not be exercisable by a Registered Holder in any state
where such exercise would be unlawful.

      This Warrant Certificate is exchangeable, upon the surrender hereof by the
Registered Holder at the corporate office of the Warrant Agent, for a new
Warrant Certificate or Warrant Certificates of like tenor representing an equal
aggregate number of Warrants, each of such new Warrant Certificates to represent
such number of Warrants as shall be designated by such Registered Holder at the
time of such surrender. Upon due presentment and payment of any tax or other
charge imposed in connection therewith or incident thereto, for registration of
transfer of this Warrant Certificate at such office, a new Warrant Certificate
or Warrant Certificates representing an equal aggregate number of Warrants will
be issued to the transferee in exchange therefor, subject to the limitations
provided in the Warrant Agreement.

      Prior to the exercise of any Warrant represented hereby, the Registered
Holder shall not be entitled to any rights of a stockholder of the Company,
including, without limitation, the right to vote or to receive dividends or
other distributions, and shall not be entitled to receive any notice of any
proceedings of the Company, except as provided in the Warrant Agreement.

      Subject to the provisions of the Warrant Agreement, this Warrant may be
redeemed at the option of the Company and with the prior consent of Gaines,
Berland Inc., at a redemption price of $.05 per Warrant, at any time commencing
after the Commencement Date, provided that the last sales price of the Common
Stock shall have, for twenty (20) consecutive trading days ending on the third
day prior to the day that the notice of redemption is given, equaled or exceeded
$10.00 per share (subject to adjustment in the event of any stock splits or
other similar events). Notice of redemption shall be given not less than the
thirtieth day before the date fixed for redemption, all as provided in the
Warrant Agreement. On and after the date fixed for redemption, the Registered
Holder shall have no rights with respect to this Warrant except to receive the
$.05 per Warrant upon surrender of this Certificate.

      In accordance with the Warrant Agreement, Gaines, Berland Inc. and
EarlyBirdCapital, Inc., collectively, shall be entitled to receive a commission
equal to 5% of the proceeds received by the Company from the exercise of the
Warrants.

      Prior to due presentment for registration of transfer hereof, the Company
and the Warrant Agent may deem and treat the Registered Holder as the absolute
owner hereof and of each Warrant represented hereby (notwithstanding any
notations of ownership or writing hereon made by anyone other than a duly
authorized officer of the Company or the Warrant Agent) for all purposes and
shall not be affected by any notice to the contrary, except as provided in the
Warrant Agreement.

      This Warrant Certificate shall be governed by and construed in accordance
with the laws of the State of New York without giving effect to conflicts of
laws.

      This Warrant Certificate is not valid unless countersigned by the Warrant
Agent.

      IN WITNESS WHEREOF, the Company has caused this Warrant Certificate to be
duly executed, manually or in facsimile by two of its officers thereunto duly
authorized and a facsimile of its corporate seal to be imprinted hereon.

Dated:                               UNITY EMERGING TECHNOLOGY VENTURE ONE LTD.


<TABLE>
<S>                                         <C>                   <C>
COUNTERSIGNED:                               By:                   By:
 AMERICAN STOCK TRANSFER & TRUST COMPANY,
                         as Warrant Agent        /s/Norman Leben       /s/Lawrence Burstein
                       Authorized Officer           SECRETARY                PRESIDENT

</TABLE>

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                   UNITY EMERGING TECHNOLOGY VENTURE ONE LTD.
                                   CORPORATE
                                      SEAL
                                      2000
                                    DELAWARE
                                       *


<PAGE>

                               SUBSCRIPTION FORM

     To Be Executed by the Registered Holder in Order to Exercise Warrants

      The undersigned Registered Holder hereby irrevocably elects to exercise
_____________ Warrants represented by this Warrant Certificate, and to purchase
the securities issuable upon the exercise of such Warrants, and requests that
certificates for such securities shall be issued in name of

                         PLEASE INSERT SOCIAL SECURITY
                          OR OTHER IDENTIFYING NUMBER

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------
                    (please print or type name and address)


and be delivered to

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

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                    (please print or type name and address)

and if such number of Warrants shall not be all the Warrants evidenced by this
Warrant Certificate, that a new Warrant Certificate for the balance of such
Warrants be registered in the name of, and delivered to, the Registered Holder
at the address stated below.

Dated:                                  X
       ----------------------------          -----------------------------------

                                             -----------------------------------

                                             -----------------------------------

                                             -----------------------------------
                                                           Address


                                             -----------------------------------
                                                 Social Security or Taxpayer
                                                    Identification Number

                                             -----------------------------------
                                                     Signature Guaranteed

                                             -----------------------------------


      The undersigned represents that the exercise of the within Warrant was
solicited by Gaines, Berland Inc. and/or EarlyBirdCapital, Inc. If not solicited
by Gaines, Berland Inc. and/or EarlyBirdCapital, Inc., please write
"unsolicited" in the space below or write the name of the broker/dealer which
solicited your exercise. Unless otherwise indicated, it will be assumed that the
exercise was solicited by Gaines, Berland Inc. and/or EarlyBirdCapital, Inc.


                                             -----------------------------------
                                             (Write "unsolicited" on above line
                                             if not solicited by Gaines, Berland
                                             Inc. and/or EarlyBirdCapital, Inc.)

Dated:                                  Signature:
       ----------------------------               ------------------------------


<PAGE>

                                   ASSIGNMENT

      FOR VALUE RECEIVED,

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hereby sells, assigns and transfers unto

                        PLEASE INSERT SOCIAL SECURITY OR
                            OTHER IDENTIFYING NUMBER

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------
                    (please print or type name and address)

___________________________ of the Warrants represented by this Warrant
Certificate, and hereby irrevocably constitutes and appoints
________________________________________________________________________
Attorney to transfer this Warrant Certificate on the books of the Company, with
full power of substitution in the premises.

Dated:                                  X
       ----------------------------          -----------------------------------
                                                    Signature Guaranteed


THE SIGNATURE TO THE ASSIGNMENT OR THE SUBSCRIPTION FORM MUST CORRESPOND TO THE
NAME AS WRITTEN UPON THE FACE OF THIS WARRANT CERTIFICATE IN EVERY PARTICULAR,
WITHOUT ALTERATION OR ENLARGEMENT OR ANY CHANGE WHATSOEVER AND MUST BE
GUARANTEED BY A COMMERCIAL BANK OR TRUST COMPANY OR A MEMBER FIRM OF THE
AMERICAN STOCK EXCHANGE, NEW YORK STOCK EXCHANGE, PACIFIC STOCK EXCHANGE OR
MIDWEST STOCK EXCHANGE.