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                                                                   EXHIBIT 10.11

                                                                  EXECUTION COPY

            THE SECURITIES EVIDENCED BY THIS INSTRUMENT HAVE NOT BEEN
          REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE
          "ACT"), AND HAVE BEEN TAKEN FOR INVESTMENT PURPOSES ONLY, AND
              NOT WITH A VIEW TO THE DISTRIBUTION THEREOF, AND SUCH
            SECURITIES MAY NOT BE SOLD, PLEDGED OR TRANSFERRED UNLESS
           THERE IS AN EFFECTIVE REGISTRATION STATEMENT UNDER THE ACT
         COVERING SUCH SECURITIES OR THE COMPANY RECEIVES AN OPINION OF
           COUNSEL (WHICH MAY BE COUNSEL FOR THE COMPANY), REASONABLY
          SATISFACTORY IN FORM AND CONTENT TO THE COMPANY, STATING THAT
                    SUCH SALE OR TRANSFER IS EXEMPT FROM THE
                      REGISTRATION AND PROSPECTUS DELIVERY
                            REQUIREMENTS OF THE ACT.

                           MICROFINANCIAL INCORPORATED

       (Incorporated under the laws of The Commonwealth of Massachusetts)

                               WARRANT CERTIFICATE

No. 5                                                         September 29, 2004

                    To Purchase 75,000 Shares of Common Stock

         This is to certify that, for value received, STONEBRIDGE ASSOCIATES,
LLC having an office at Ten Post Office Square, Suite 1330, Boston,
Massachusetts 02109 ("STONEBRIDGE"), or any subsequent holder hereof
(collectively with STONEBRIDGE, the "HOLDER"), is entitled to purchase from
MICROFINANCIAL INCORPORATED a Massachusetts corporation (the "COMPANY"), in
whole or in part, at an exercise price of $3.704 per share, subject to
adjustment as hereinafter provided (the "EXERCISE PRICE"), at any time after
9:00 a.m. (Boston time) on the date hereof (the "EXERCISABLE DATE") and prior to
5:00 p.m. (Boston time) on September 28, 2011, (the "EXPIRATION DATE"), 75,000
shares of fully paid and non-assessable shares of the Common Stock $0.01 par
value, of the Company (the "COMMON STOCK"). As used herein, the period from the
Exercisable Date through the Expiration Date shall be the "EXERCISE PERIOD".
This Warrant Certificate, any other warrants issued as provided herein and any
other warrants issued as provided in the Warrant Purchase Agreement (as defined
below), are hereinafter collectively referred to as the "WARRANTS" and all
shares of Common Stock and other securities purchased or purchasable upon
exercise of this Warrant are hereinafter collectively referred to as "WARRANT
SHARES." The number of shares of Common Stock and the Exercise Price are subject
to adjustment as hereinafter set forth.

         SECTION 1.  EXERCISE OF WARRANT.

         1.1 Time and Manner of Exercise. This Warrant may be exercised by the
Holder hereof, in whole or in part, any time during the Exercise Period by
surrender of this Warrant,

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with the form of subscription attached hereto (the "SUBSCRIPTION") completed and
duly executed by such Holder, to the Company at its principal office at 10-M
Commerce Way, Woburn, Massachusetts 01801, or at such other address as the
Company may designate by notice in writing to the Holder hereof at the address
of such Holder on the books of the Company. Notwithstanding the foregoing, the
Holder may only exercise this Warrant in part if the Holder is exercising for at
least 15,000 Warrant Shares (as adjusted for stock splits, stock dividends,
subdivisions and the like) or all Warrant Shares represented by this Warrant, if
less than 15,000 Warrant Shares (as adjusted for stock splits, stock dividends,
subdivisions and the like) remain outstanding in the aggregate.

         1.2 Payment. Payment in an amount equal to the product of (a) the
number of shares of Common Stock designated in the Subscription, times (b) the
Exercise Price shall be due to the Company, in cash or by certified or official
bank check payable to the Company within five (5) Business Days after the date
of exercise.

         1.3 When Exercise Effective. Each exercise of this Warrant shall be
deemed to have been effected immediately prior to the close of business on the
Business Day on which this Warrant shall have been surrendered to the Company as
provided in subsection 1.1, and at such time the person or persons in whose name
or names any certificate or certificates for shares of Common Stock (or of the
other securities or property to which such Holder is entitled upon such exercise
in accordance with the terms hereof) shall be issuable upon such exercise as
provided in subsection 1.2, shall be deemed to have become the Holder or Holders
of record thereof.

         1.4 Delivery of Stock Certificates, etc. As soon as practicable after
the exercise of this Warrant, in whole or in part, and in any event within 10
days thereafter, the Company at its expense will cause to be issued in the name
of and delivered to the Holder hereof, or as such Holder may direct:

                  (a) a certificate or certificates for the number of full
shares of Common Stock to which such Holder shall be entitled upon such exercise
plus, in lieu of any fractional share to which such Holder would otherwise be
entitled, cash in an amount equal to the same fraction of the Exercise Price of
one full share of Common Stock, which shall be paid to the Holders thereof on
the Business Day next preceding the date of such exercise;

                  (b) in case such exercise is in part only, a new Warrant or
Warrants of like tenor, for the number of shares of Common Stock in respect of
which this Warrant shall not have been exercised;

                  (c) each certificate representing shares of Common Stock
issued upon exercise of this Warrant shall be stamped or otherwise imprinted
with a legend substantially in the following form (in addition to, or in
combination with, any other legend required under applicable state securities
law and agreements or by-law provisions relating to the transfer of the
Company's securities):

    THE SHARES EVIDENCED BY THIS CERTIFICATE HAVE NOT BEEN REGISTERED UNDER
              THE SECURITIES ACT OF 1933, AS AMENDED (THE "ACT"),

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AND HAVE BEEN TAKEN FOR INVESTMENT PURPOSES ONLY, AND NOT WITH A VIEW TO THE
DISTRIBUTION THEREOF, AND SUCH SECURITIES MAY NOT BE SOLD, PLEDGED OR
TRANSFERRED UNLESS THERE IS AN EFFECTIVE REGISTRATION STATEMENT UNDER THE ACT
COVERING SUCH SECURITIES OR THE COMPANY RECEIVES AN OPINION OF COUNSEL (WHICH
MAY BE COUNSEL FOR THE COMPANY), REASONABLY SATISFACTORY IN FORM AND CONTENT TO
THE COMPANY, STATING THAT SUCH SALE OR TRANSFER IS EXEMPT FROM THE REGISTRATION
AND PROSPECTUS DELIVERY REQUIREMENTS OF THE ACT.

         SECTION 2.  INVESTMENT REPRESENTATIONS.

         The Holder hereof understands that this Warrant (and the Common Stock
issuable upon exercise of this Warrant) to be purchased by such Holder have not
been registered under the Securities Act of 1933, as amended (the "SECURITIES
ACT"), or any similar federal statute, and the rules and regulations of the
Securities and Exchange Commission, or any other federal agency at the time
administering the Securities Act by reason of a specific exemption from the
registration provisions of the Securities Act which depends upon, among other
things, the bona fide nature of the investment intent as expressed herein. The
Holder further understands that neither this Warrant nor the Common Stock
issuable upon the exercise of this Warrant may be offered, sold or otherwise
transferred, pledged or hypothecated unless or until this Warrant or the Common
Stock issuable upon the exercise of this Warrant, as the case may be, is
registered under the Securities Act or an exemption form such registration is
available. The Holder hereof has had an opportunity to discuss the Company's
business, management and financial affairs with the Company's management and to
obtain any additional information necessary to verify the accuracy of the
information given to such Holder. The Holder hereof represents that such Holder
is an accredited investor under Rule 501(a) of Regulation D of the Securities
Act and that such Holder is able to bear the economic risk of such Holder's
investment in the Company contemplated hereby. The Holder is acquiring this
Warrant for its own account for investment purposes without a view to any
distribution thereof in violation of the Securities Act.

         SECTION 3. MAINTENANCE OF WARRANT REGISTER; ASSIGNMENT AND TRANSFER AND
REPLACEMENT.

         3.1 Registered Holders. The Company will maintain a register containing
the name and address of the Holder of this Warrant. The "REGISTERED HOLDER" of
this Warrant shall be the person in whose name such Warrant is registered in
said warrant register. Any registered Holder of this Warrant may change such
Holder's address as shown on the warrant register by written notice to the
Company requesting such change. Any notice or written communication required or
permitted to be given to the registered Holder of this Warrant shall be mailed,
by certified or registered mail, return receipt requested, postage prepaid, or
delivered to such registered Holder at its address as shown on the warrant
register.

         3.2 Assignment and Transfer of the Warrant. Subject to Section 9 and on
the basis of the foregoing representations set forth in Section 2 above, this
Warrant has not been registered under the Securities Act, and neither this
Warrant nor the rights evidenced hereby shall be assigned, pledged, transferred
or otherwise disposed of unless either (a) this Warrant first shall

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have been registered under the Securities Act, or (b) the Company first shall
have been furnished with an opinion of legal counsel reasonably satisfactory to
the Company stating that such sale or transfer is an exempted transaction under
the Securities Act and, unless such opinion states that such Warrant may be
transferred by the transferee immediately after acquisition without registration
under the Securities Act, a written agreement by the transferee thereof not to
sell or transfer such Warrant without complying with the requirements provided
for in this subsection 3.2. Upon surrender of this Warrant to the Company for
transfer as an entirety by the registered Holder (as permitted by this Section)
at the offices of the Company referred to in Section 1.1 hereof, with the form
of assignment attached hereto completed and duly executed by the registered
Holder, the Company shall, at the Company's expense, issue a new Warrant of the
same denomination to the assignee.

         3.3 Replacement. In case this Warrant shall be mutilated, lost, stolen,
or destroyed, the Company shall issue a new Warrant of like tenor and
denomination and deliver the same at the holder's expense (a) in exchange and
substitution for and upon surrender and cancellation of the mutilated Warrant,
or (b) in lieu of the Warrant lost, stolen or destroyed, upon receipt of (i) a
reasonably detailed affidavit with respect to the circumstances of any loss,
theft or destruction, and (ii) an indemnity reasonably satisfactory to the
Company.

         SECTION 4.  ADJUSTMENT OF STOCK ISSUABLE UPON EXERCISE.

         4.1 Adjustment for Subdivisions, Combinations or Consolidation of
Common Stock. If the outstanding shares of Common Stock are subdivided by stock
split, stock dividends or otherwise, into a greater number of shares of Common
Stock, concurrently with the effectiveness of such subdivision, the Exercise
Price then in effect shall be proportionately decreased and the number of
Warrant Shares shall be proportionately increased so that the number of shares
of Common Stock issuable upon the exercise of this Warrant shall be increased in
proportion to such increase in outstanding shares of Common Stock and the
aggregate consideration payable upon the exercise of this Warrant with respect
to the Warrant Shares before giving effect to such subdivision shall not change.
If the outstanding shares of Common Stock shall be combined or consolidated, by
reclassification or otherwise, into a lesser number of shares of Common Stock,
concurrently with the effectiveness of such combination or consolidation, the
Exercise Price then in effect shall be proportionately increased and the number
of Warrant Shares shall be proportionately decreased so that the number of
shares of Common Stock issuable upon the exercise of this Warrant shall be
decreased in proportion to such decrease in outstanding shares of Common Stock
and the aggregate consideration payable upon the exercise of this Warrant with
respect to the Warrant Shares before giving effect to such combination or
consolidation shall not change.

         4.2 No Impairment. The Company will not, by amendment of its
certificate of incorporation or through reorganization, consolidation, merger,
dissolution, issue or sale of securities, sale of assets or any other voluntary
action, avoid or seek to avoid the observance or performance of any of the terms
of the Warrants, but will at all times in good faith assist in the carrying out
of all such terms and in the taking of all such action as may be necessary or
appropriate in order to protect the rights of the Holders of the Warrants
hereunder against impairment. Without limiting the generality of the foregoing,
the Company (a) will not increase

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the par value of any share of stock receivable upon the exercise of the Warrants
above the amount payable therefor upon such exercise, and (b) will take all such
action as may be necessary or appropriate in order that the Company may validly
and legally issue fully paid and non-assessable shares upon the exercise of all
Warrants at the time outstanding.

         4.3 Certificate as to Adjustment. In each case of an adjustment in the
number of shares of Common Stock or the number or type of other stock,
securities or property receivable on the exercise of the Warrants, the Company
at its expense shall cause its chief financial officer (who may be the
independent public accountants then auditing the books of the Company) to
compute such adjustment in accordance with the terms of the Warrants and prepare
a certificate setting forth such adjustment and showing in detail the facts upon
which such adjustment is based, including a statement of (a) the number of
Warrant Shares issuable upon exercise of this Warrant, and (b) the Exercise
Price. The Company will forthwith mail a copy of each such certificate to each
Holder of a Warrant at the time outstanding.

         4.4. Notices of Record Date: In case:

                  (a) the Company shall take a record of the Holders of its
Common Stock (or other stock or securities at the time receivable upon the
exercise of the Warrants) for the purpose of any stock split, stock dividend,
subdivision, combination or consolidation, or

                  (b) of any capital reorganization of the Company, any
reclassification of the capital stock of the Company, any consolidation or
merger of the Company with or into another person, or any conveyance of all or
substantially all of the assets of the Company to another person, or

                  (c) of any voluntary dissolution, liquidation or winding-up of
the Company, then, and in each such case, the Company will mail or cause to be
mailed to each Holder of a Warrant at the time outstanding a notice specifying,
as the case may be, (i) the date on which a record is to be taken for the
purpose of any stock split, stock dividend, subdivision, combination or
consolidation, or (ii) the date on which such reorganization, reclassification,
consolidation, merger, conveyance, dissolution, liquidation or winding-up is
expected to take place, and the time, if any is to be fixed, as of which the
Holders of record of Common Stock (or such stock or securities at the time
receivable upon the exercise of the Warrants) shall be entitled to exchange
their shares of Common Stock (or such other stock or securities) for securities
or other property deliverable upon such reorganization, reclassification,
consolidation, merger, conveyance, dissolution, liquidation or winding-up. Such
notice shall be mailed at least twenty (20) days prior to the date specified in
the notice on which any such action is to be taken.

         4.5 Adjustments For Consolidation, Merger, Sale of Assets,
Reorganization, Etc. If the Company effects a capital reorganization or
reclassification of the stock of the Company (other than a change in par value
or as a result of a stock dividend or subdivision, split-up or combination of
shares), or the consolidation or merger of the Company with or into another
person (other than a consolidation or merger in which the Company is the
continuing corporation and which does not result in any change in the Common
Stock), or sells or otherwise disposes of all or substantially all the
properties and assets of the Company as an entirety to any other

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person, the Holder of this Warrant, upon the exercise hereof at any time after
the consummation of such reorganization, reclassification, consolidation,
merger, sale or other disposition, shall be entitled to receive, in lieu of the
Common Stock issuable upon such exercise prior to such consummation, the kind
and number of shares of stock or other securities or property of the Company or
of the corporation resulting from such consolidation or surviving such merger or
to which such properties and assets shall have been sold or otherwise disposed
to which such Holder would have been entitled if immediately prior to such
reorganization, reclassification, consolidation, merger, sale or other
disposition such Holder had exercised this Warrant. The provisions of this
subsection 4.5 shall similarly apply to successive reorganizations,
reclassifications, consolidations, mergers, sales or other dispositions. The
Company shall not effect any such merger, consolidation, or similar
reorganization in which the Company does not survive or in which its Common
Stock changes, unless prior to or simultaneously with the consummation thereof
the successor corporation shall assume by written instrument executed and mailed
or delivered to the Holder of this Warrant at the last address of such Holder
appearing on the books of the Company, the obligations to deliver to such Holder
such shares of stock, securities or assets as, in accordance with the foregoing
provisions, such Holder may be entitled to purchase.

         4.6 Dissolution. In the event of any dissolution of the Company
following the transfer of all or substantially all of its properties or assets,
the Company, prior to such dissolution, shall at its expense deliver or cause to
be delivered the stock and other securities and property (including cash, where
applicable) receivable by the holders of this Warrant after the effective date
of such dissolution pursuant to this Section 4 to a bank or trust company as a
trustee for the holders of this Warrant.

         4.7 Continuation of Terms. Upon any reorganization, consolidation,
merger or transfer (and any dissolution following any transfer) referred to in
this Section 4, this Warrant shall continue in full force and effect and the
terms hereof shall be applicable to the shares of stock and other securities and
property receivable on the exercise of this Warrant after the consummation of
such reorganization, consolidation, or merger or the effective date of
dissolution following any such transfer, as the case may be, and shall be
binding upon the issuer of any stock or other securities, including in the case
of any such transfer, the person acquiring all or substantially all of the
properties or assets of the Company, whether or not such person shall have
expressly assumed the terms of this Warrant.

         4.8 Calculations Made to Nearest Cent or Full Share. All calculations
under this Section 4 shall be made to the nearest cent or to the nearest full
share, as the case may be (with one-half of a cent or a share being rounded to
the next highest full cent or share).

         SECTION 5.  OTHER NOTICES.  In case at any time:

                  (a) the Company shall declare any dividend or other
distribution upon its Common Stock payable in stock to the Holders of its Common
Stock; or

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                  (b) the Company shall propose a subdivision of its outstanding
Common Stock into a greater number of shares of Common Stock or propose a
combination of its outstanding Common Stock into a smaller number of shares of
Common Stock; or

                  (c) the Company shall propose any capital reorganization or
any reclassification of capital stock of the Company or any consolidation,
merger or sale of all or substantially all of its properties and assets; or

                  (d) there shall be a voluntary or involuntary dissolution,
liquidation or winding-up of the Company; then, and in each of said cases, the
Company shall cause notice thereof to be mailed to the Holder of this Warrant at
the last address appearing on the books of the Company or given by such Holder
to the Company for the purpose of notice. Such notices shall be mailed at least
twenty (20) days prior to the date on which the books of the Company shall
close, or a record date shall be taken for such dividend, distribution, stock
split or combination or issue of rights or to vote upon such capital
reorganization, reclassification, consolidation, merger or sale of properties
and assets, as the case may be, and shall specify such record date or date for
the closing of the transfer books.

         SECTION 6.  RESERVATION OF STOCK ISSUABLE UPON EXERCISE.

         The Company shall at all times reserve and keep available out of its
authorized but unissued shares of Common Stock, solely for issuance and delivery
upon the exercise of this Warrant, such number of its shares of Common Stock as
shall from time to time be issuable upon the exercise of this Warrant; and if at
any time the number of authorized but unissued shares of its Common Stock shall
not be sufficient for such purpose, the Company will take such corporate actions
as may, in the opinion of its counsel, be necessary to increase its authorized
but unissued shares of its Common Stock to such number of shares as shall be
sufficient for such purpose.

         SECTION 7.  RIGHTS AS STOCKHOLDER.

         The registered Holder of this Warrant, as such, shall not be entitled
to vote or receive dividends or be deemed the Holder of shares of Common Stock
for any purpose, nor shall anything contained in this Warrant be construed to
confer upon the registered Holder of this Warrant, as such, any of the rights of
a stockholder of the Company or any right to vote, give or withhold consent to
any action by the Company (whether upon any recapitalization, issue of shares,
reclassification of shares, consolidation, merger, conveyance or otherwise),
receive notice of meetings or other action affecting stockholders (except for
notices provided for in this Warrant), receive dividends or subscription rights,
or otherwise until this Warrant shall have been exercised and the shares of
Common Stock purchasable upon the exercise hereof shall have become deliverable
as provided in Section 1 hereof, at which time the person or persons in whose
name or names the certificate or certificates for the shares of Common Stock
being purchased are to be issued shall be deemed the holder or holders of record
of shares of Common Stock for all purposes.

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         SECTION 8.  REMEDIES.

         The Company stipulates that the remedies at law of the Holder of this
Warrant in the event of any default or threatened default by the Company in the
performance of or compliance with any of the terms of this Warrant are not and
will not be adequate, and that such terms may be specifically enforced by a
decree for the specific performance of any agreement contained herein or by an
injunction against a violation of any of the terms hereof or otherwise.

         SECTION 9.  TRANSFERABILITY.

         This Warrant may be transferred or assigned in whole or in part by the
Holder either to an affiliate (as that term is defined in the Securities Act) of
the Holder or to anyone else except for a competitor if the Holder has complied
with the terms and conditions of (i) this Warrant and (ii) all applicable
federal and state securities laws; provided however that (other than in the case
of a transfer or assignment of this Warrant to an affiliate of the Holder), such
compliance shall include, without limitation, the delivery of investment
representation letters and legal opinions reasonably satisfactory to the
Company. Subject to the provisions of this Warrant with respect to compliance
with the Securities Act, title to this Warrant may be transferred by endorsement
(by the Holder executing the Form of Assignment annexed hereto) and delivery in
the same manner as a negotiable instrument transferable by endorsement and
delivery. For purposes of this Agreement, "competitor" shall mean any company
that is primarily engaged in the business of manufacturing, selling, licensing
or developing products that are competitive with products being manufactured,
sold, leased, developed or licensed by the Company or any Subsidiary on or after
the date hereof. Notwithstanding the foregoing, this Warrant may only be
assigned in part if the Holder is assigning the right to receive at least 15,000
Warrant Shares (as adjusted for stock splits, stock dividends, subdivisions and
the like) or all Warrant Shares represented by this Warrant if less than 15,000
Warrant Shares (as adjusted for stock splits, stock dividends, subdivisions and
the like) remain outstanding in the aggregate.

         SECTION 10.  NOTICES, ETC.

         All notices and other communications from the Company to the Holder of
this Warrant shall be mailed by recognized overnight courier first class
registered or certified air mail, postage prepaid, at such address as may have
been furnished to the Company in writing by such Holder, or, until an address is
so furnished, to and at the address of the last Holder of this Warrant who has
so furnished an address to the Company.

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         SECTION 11.  MISCELLANEOUS.

         This Warrant and any term hereof may be changed, waived, discharged or
terminated only by an instrument in writing signed by the party against which
enforcement of such change, waiver, discharge or termination is sought. This
Warrant is being delivered in The Commonwealth of Massachusetts and shall be
construed and enforced in accordance with and governed by the laws of such
commonwealth. All section headings herein are for purposes of reference only and
shall not limit or otherwise affect the meaning hereof. The invalidity or
unenforceability of any provision hereof shall in no way affect the validity or
unenforceability of any other provision. For purposes of this Warrant, the term
"Business Day" shall mean a day other than a Saturday, Sunday or any day on
which commercial banks in Boston, Massachusetts are authorized or required by
law to close.

         IN WITNESS WHEREOF, MICROFINANCIAL INCORPORATED has caused this
instrument to be duly executed by its duly authorized officer this 29th day of
September, 2004.

Attest:                                        MICROFINANCIAL INCORPORATED

____________________________________________   By:______________________________
James R. Jackson , Chief Financial Officer        Richard F. Latour, President

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ELECTION TO PURCHASE

MICROFINANCIAL INCORPORATED
10-M Commerce Way
Woburn, Massachusetts 01801

Ladies and Gentlemen:

         The undersigned hereby subscribes for _______ shares of the Common
Stock of MICROFINANCIAL INCORPORATED covered by the within Warrant and tenders
payment herewith in the amount of $________________ in accordance with the terms
thereof.

         Such payment is hereby tendered in the form of $ in cash or certified
or bank check.

         You are instructed as follows:

         1. To issue certificate(s) for said shares to

            Name:

            Address:

         2. To deliver said certificate(s) by registered mail, return receipt
            requested, to

            Name:

            Address:

                                           Very truly yours,

                                           [INSERT HOLDER]

                                           _____________________________________
                                           Name:
                                           Title:
                                           Address:

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                               FORM OF ASSIGNMENT

[To be signed only upon transfer of Warrant]

For value received, the undersigned hereby sells, assigns and transfers unto
____________ _______________________________ the right represented by the within
Warrant to purchase ___________ shares of Common Stock of MICROFINANCIAL
INCORPORATED to which the within Warrant relates, and appoints
_____________________ Attorney to transfer such right on the books of
MICROFINANCIAL INCORPORATED with full power of substitution in the premises.

Dated:

                         _______________________________________________________
                         (Signature must conform in all respects to name of
                         Holder as specified on the face of the Warrant)

(Address)

Signed in the presence of:

______________________________________

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