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                                UNIT CERTIFICATE

                                      FRONT

1. Logo: MILESTONE SCIENTIFIC  (Same as Common Stock Certificate.)

2. Certificate Number: Should have the prefix:  "U"

3. CUSIP NO.: "____________."

4. Centered below the Logo:

                ORGANIZED UNDER THE LAWS OF THE STATE OF delaware
               EACH UNIT CONSISTING OF TWO SHARES OF COMMON STOCK,
              AND ONE WARRANT TO PURCHASE ONE SHARE OF COMMON STOCK

5. In the shaded area:

"THIS CERTIFIES THAT __________________________"

6. Below the shaded area:

"or registered assigns (the "Registered Holder") is the owner of the number of
Units specified above. Each Unit ("Unit") consists of two (2) shares of common
stock, $.001 par value (the "Common Stock"), of Milestone Scientific Inc. (the
"Company") and one (1) redeemable warrant (the "Warrant") to purchase one share
of Common Stock for $_____________ per share (subject to adjustment) until 5:00
p.m. Eastern Time ______________ 2009. On or prior to the Separation Time (as
defined below), the securities evidenced by this certificate cannot be traded
separately. Each Unit will automatically separate into two shares of Common
Stock and one Warrant as of the close of business on ______________, 2004 (the
"Separation Time"). The Common Stock and the Warrants comprising the Units shall
be separately tradable commencing on the first day after the Separation Time on
which the principal exchange on which the Company's stock trades is open for
trading. The Warrants comprising part of the Units are issued under and pursuant
to a certain Warrant Agreement dated as of ______________, 2004 (the "Warrant
Agreement"), between the Company and Continental Stock Transfer & Trust Company,
as Warrant Agent (the "Warrant Agent"), and are subject to the terms and
provisions contained therein and on the face of the certificates covered
thereby, to all of which terms and provisions the holder of this Unit
Certificate consents by acceptance hereof. The Warrant Agreement provides for
adjustment in the number of shares of Common Stock to be delivered upon the
exercise of the Warrant evidenced hereby and to the exercise price of such
Warrant in certain events therein set forth.

     Copies of the Warrant Agreement are available for inspection at the stock
transfer office of the Warrant Agent or may be obtained upon written request
addressed to the Company at 220 South Orange Avenue, Livingston, NJ 07039,
Attention: Chief Financial Officer.

     This Unit Certificate is not valid unless countersigned by the Transfer
Agent and Registrar of the Company."

7. Signatures: Same as Common Stock Certificate, including Transfer Agent.

8. Corporate Seal: Same as Common Stock Certificate.


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BACK

MILESTONE SCIENTIFIC INC.

     The Registered Holder hereby is entitled, at any time, to exchange the
Units represented by this Unit Certificate for Common Stock Certificate(s)
representing two shares of Common Stock, for each Unit represented by this Unit
Certificate and one Warrant Certificate representing one Warrant, for each Unit
represented by this Unit Certificate, upon surrender of this Unit Certificate to
the Transfer Agent and Registrar together with any documentation required by
such agent.

     REFERENCE IS MADE TO THE WARRANT AGREEMENT REFERRED TO ON THE FACE HEREOF,
AND THE PROVISIONS OF SUCH WARRANT AGREEMENT SHALL FOR ALL PURPOSES HAVE THE
SAME EFFECT AS THOUGH FULLY SET FORTH ON THE FACE OF THIS CERTIFICATE. COPIES OF
THE WARRANT AGREEMENT MAY BE OBTAINED UPON WRITTEN REQUEST FROM THE TRANSFER
AGENT AND REGISTRAR, CONTINENTAL stock transfer & trust company.

     The following abbreviations, when used in the inscription on the face of
this certificate, shall be construed as though they were written out in full
according to applicable laws or regulations.

     TEN COM  as tenants in common
     TEN ENT  as tenants by the entireties
     JT TEN   as joint tenants with rights of survivorship and not as tenants
              in common
     COM PROP as community property

UNIF GIFT MIN ACT          _________________     Custodian      _______________
                           (Cust)                              (minor)
                           under Uniform Gifts to Minors Act

                           __________________________________________
                                               (State)

UNIF TRF MIN ACT           ________________      Custodian      _______________
                           (Cust)                              (minor)
                           under Uniform Gifts to Minors Act 3

                           __________________________________________
                                              (State)

                               FORM OF ASSIGNMENT
                       (TO BE SIGNED ONLY UPON ASSIGNMENT)

FOR VALUE RECEIVED, the undersigned Registered Holder

(------------------------)
(Please insert social security or other identification number of Registered
 Holder)

hereby sells, assigns and transfers unto
______________________________________________________________________________
               (Please Print Name and Address including Zip Code)

Units evidenced by the within Unit Certificate, and irrevocably constitutes and
appoints ______________________________________________________________________
attorney to transfer this Unit Certificate on the books of Milestone Scientific
Inc. with the full power of substitution in the premises.

Dated:   __________________, ________
Signature: __________________________________
(Signature must conform in all respects to the name of Registered Holder as
specified on the face of this Unit Certificate in every particular, without
alteration or any change whatsoever, and the signature must be guaranteed in the
usual manner.)

Signatures Guaranteed:

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The signatures should be guaranteed by an eligible institution (banks,
stockbrokers, savings and loan association and credit unions with membership in
an approved signature medallion program), pursuant to S.E.C. Rule 17Ad-15.