Exhibit 4.2

THIS WARRANT AND THE SHARES OF COMMON STOCK ISSUABLE UPON EXERCISE OF THIS
WARRANT HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED.
THIS WARRANT AND THE SHARES OF COMMON STOCK ISSUABLE UPON EXERCISE OF THIS
WARRANT MAY NOT BE SOLD, OFFERED FOR SALE, PLEDGED OR HYPOTHECATED IN THE
ABSENCE OF AN EFFECTIVE REGISTRATION STATEMENT AS TO THIS WARRANT UNDER SAID ACT
OR ANY APPLICABLE STATE SECURITIES LAW OR AN OPINION OF COUNSEL REASONABLY
SATISFACTORY TO COMPANY THAT SUCH REGISTRATION IS NOT REQUIRED, EXCEPT THAT
THESE SECURITIES MAY BE PLEDGED IN CONNECTION WITH A BONA FIDE MARGIN ACCOUNT OF
THE HOLDER WITH A REGISTERED BROKER-DEALER OR OTHER LOAN OF THE HOLDER WITH A
FINANCIAL INSTITUTION THAT IS AN "ACCREDITED INVESTOR" AS DEFINED IN RULE501(a)
UNDER THE SECURITIES ACT

               VOID AFTER 5 P.M. PACIFIC TIME ON FEBRUARY 16, 2009

                        WARRANTS TO PURCHASE COMMON STOCK

No. MSW-D-                                                          [ ] Warrants

                            Milestone Scientific Inc.

THIS CERTIFIES THAT:

                                     [name]

or registered assigns, is the registered holder of the number of Warrants
("Warrants") set forth above. Each Warrant, unless and until redeemed by the
Company as provided in the Warrant Agreement, hereinafter more fully described
(the "Warrant Agreement") entitles the holder thereof to purchase from Milestone
Scientific Inc., a corporation incorporated under the laws of the State of
Delaware (the "Company"), subject to the terms and conditions set forth
hereinafter and in the Warrant Agreement, at any time before the close of
business on February 16, 2009 ("Expiration Date"), one fully paid and
non-assessable share of Common Stock, par value $0.001 per share, of the Company
("Common Stock") upon presentation and surrender of this Warrant Certificate,
with the instructions for the registration and delivery of Common Stock filled
in, at the offices of the Company, 230 South Orange Avenue, Livingston, New
Jersey 07039, and upon payment of the Exercise Price (as defined in the Warrant
Agreement) and any applicable taxes paid either in cash, or by certified or
official bank check, payable in lawful money of the United States of America to
the order of the Company. Each Warrant initially entitles the holder to purchase
one share of Common Stock for $4.89. The number and kind of securities or other
property for which the Warrants are exercisable are subject to adjustment in
certain events, such


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as mergers, splits, stock dividends, splits and the like, to prevent dilution.
The Company may redeem any or all outstanding and unexercised warrants by giving
not less than 30 days prior notice at any time after the closing price of the
Common Stock on the principal exchange on which it is traded has equaled or
exceeded $6.52 per share for any five consecutive trading days; provided that
the shares of Common Stock underlying the Warrants are saleable pursuant to an
effective registration statement under the Securities Act of 1933 at all times
from the commencement of the five trading day period through the date of
redemption. The Redemption Price is $0.25 per Warrant (subject to adjustment in
the event of a stock split, dividend or the like). All Warrants not theretofore
exercised will expire on the Expiration Date.

      This Warrant, although not issued pursuant to the Warrant Agreement, is,
nevertheless, subject to all of the terms, provisions and conditions of the
Warrant Agreement, dated as of February 17, 2004, between the Company and the
Warrant Agent, to all of which terms, provisions and conditions the registered
holder of this Warrant Certificate consents by acceptance hereof. The Warrant
Agreement is incorporated herein by reference and made a part hereof and
reference is made to the Warrant Agreement for a full description of the rights,
limitations of rights, obligations, duties and immunities of the Warrant Agent,
the Company and the holders of the Warrant Certificates. Copies of the Warrant
Agreement are available upon written request addressed to the Company at
Milestone Scientific Inc., 220 South Orange Ave., Livingston, New Jersey 07039,
Attention: Chairman.

      The Company shall not be required upon the exercise of the Warrants
evidenced by this Warrant Certificate to issue fractions of Warrants, Common
Stock or other securities, but shall make adjustment therefor in cash on the
basis of the current market value of any fractional interest as provided in the
Warrant Agreement.

      In certain cases, the sale of securities by the Company upon exercise of
Warrants may violate the securities laws of the United States, certain states
thereof or other jurisdictions. The Company has agreed to use all commercially
reasonable efforts to cause a registration statement to continue to be effective
during the term of the Warrants with respect to such sales under the Securities
Act of 1933, and to take such action under the laws of various states as may be
required to cause the sale of securities upon exercise to be lawful. However,
the Company will not be required to honor the exercise of Warrants if, in the
opinion of the Board of Directors, upon advice of counsel, the sale of
securities upon such exercise would be unlawful. In certain cases, the Company
may, but is not required to, purchase Warrants submitted for exercise for a cash
price equal to the difference between the market price of the securities
obtainable upon such exercise and the exercise price of such Warrants.

      This Warrant Certificate, with or without other Certificates, upon
surrender to the Warrant Agent, any successor warrant agent or, in the absence
of any successor warrant agent, at the corporate offices of the Company, may be
exchanged for another Warrant Certificate or Certificates evidencing in the
aggregate the same number of Warrants as the Warrant Certificate or Certificates
so surrendered. If the Warrants evidenced by this Warrant Certificate shall be
exercised in part, the holder hereof shall be entitled to receive upon surrender
hereof another Warrant Certificate or Certificates evidencing the number of
Warrants not so exercised.

      No holder of this Warrant Certificate, as such, shall be entitled to vote,
receive dividends


<PAGE>

or be deemed the holder of Common Stock or any other securities of the Company
which may at any time be issuable on the exercise hereof for any purpose
whatsoever, nor shall anything contained in the Warrant Agreement or herein be
construed to confer upon the holder of this Warrant Certificate, as such, any of
the rights of a stockholder of the Company or any right to vote for the election
of directors or upon any matter submitted to stockholders at any meeting thereof
or give or withhold consent to any corporate action (whether upon any matter
submitted to stockholders at any meeting thereof, or give or withhold consent to
any merger, recapitalization, issuance of stock, reclassification of stock,
change of par value or change of stock to no par value, consolidation,
conveyance or otherwise) or to receive notice of meetings or other actions
affecting stockholders (except as provided in the Warrant Agreement) or to
receive dividends or subscription rights or otherwise until the Warrants
evidenced by this Warrant Certificate shall have been exercised and the Common
Stock purchasable upon the exercise thereof shall have become deliverable as
provided in the Warrant Agreement.

      If this Warrant Certificate shall be surrendered for exercise within any
period during which the transfer books for the Company's Common Stock or other
class of stock purchasable upon the exercise of the Warrants evidenced by this
Warrant Certificate are closed for any purpose, the Company shall not be
required to make delivery of certificates for shares purchasable upon such
transfer until the date of the reopening of said transfer books.

      Every holder of this Warrant Certificate by accepting the same consents
and agrees with the Company, the Warrant Agent, and with every other holder of a
Warrant Certificate that:

      (a) this Warrant Certificate is transferable on the registry books of the
Warrant Agent only upon the terms and conditions set forth in the Warrant
Agreement, and

      (b) the Company and the Warrant Agent may deem and treat the person in
whose name this Warrant Certificate is registered as the absolute owner hereof
(notwithstanding any notation of ownership or other writing thereon made by
anyone other than the Company or the Warrant Agent) for all purposes whatsoever
and neither the Company nor the Warrant Agent shall be affected by any notice to
the contrary. The Company shall not be required to issue or deliver any
certificate for shares of Common Stock or other securities upon the exercise of
Warrants evidenced by this Warrant Certificate until any tax which may be
payable in respect thereof by the holder of this Warrant Certificate pursuant to
the Warrant Agreement shall have been paid, such tax being payable by the holder
of this Warrant Certificate at the time of surrender.

      This Warrant Certificate shall not be valid or obligatory for any purpose
until it shall have been countersigned by the Warrant Agent.

      (Remainder of page intentionally left blank; signature page follows)

<PAGE>

      WITNESS the facsimile signatures of the proper officers of the Company and
its corporate seal.

Dated: _______________

                                 MILESTONE SCIENTIFIC INC.


                                 By:
                                     --------------------------------------
                                     Name:  Leonard Osser
                                     Title: Chairman and Chief Executive Officer


                                 Attest:
                                         ----------------------------------
                                         Assistant Secretary