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                                                                   EXHIBIT 10.21

THIS NOTE, AND ANY SHARES ISSUED IN CONNECTION HEREWITH OR IN CONSIDERATION
HEREOF, HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933 (THE
"SECURITIES ACT") NOR UNDER ANY STATE SECURITIES LAW AND MAY NOT BE PLEDGED,
SOLD, ASSIGNED OR OTHERWISE TRANSFERRED UNTIL (1) A REGISTRATION STATEMENT UNDER
THE SECURITIES ACT AND ANY APPLICABLE STATE SECURITIES LAW HAS BECOME EFFECTIVE
WITH RESPECT THERETO, OR (2) RECEIPT BY THE COMPANY OF AN OPINION OF COUNSEL TO
THE COMPANY TO THE EFFECT THAT REGISTRATION UNDER THE SECURITIES ACT OR
APPLICABLE STATE SECURITIES LAW IS NOT REQUIRED IN CONNECTION WITH THE PROPOSED
TRANSFER.

                       METROPOLITAN HEALTH NETWORKS, INC.

                  Non-Negotiable Promissory Note Due __________

$___________                                                              (DATE)
                                                        West Palm Beach, Florida

         FOR VALUE RECEIVED, METROPOLITAN HEALTH NETWORKS, INC., a corporation
duly organized and existing under the laws of the State of Florida (the
"Company") having its principal office at 500 Australian Avenue South, Suite
1000, West Palm Beach, FL 33401, hereby promises to pay to
__________________________, ________________ Dollars ($_______), with interest
at 8% per annum payable ____________.

                  The following events which shall have occurred and be
continuing are deemed to be an "Event of Default":

         (i) The Company shall default in the payment of the principal sum of
this Note after the same shall have become due and payable; or

         (ii) Commencement of any proceeding or the taking of any other action
against the Company in bankruptcy or seeking reorganization, arrangement,
readjustment of its debts, liquidation, dissolution, arrangement, composition,
readjustment of debt or any other similar act or law of any jurisdiction,
domestic or foreign, now or hereafter existing and the continuance of any of
such events for sixty (60) days undismissed, unbonded or undischarged; or the
appointment of a receiver, conservator, trustee or similar officer for the
Company or for all or substantially all of its property and the continuance of
any of such events for sixty (60) days undismissed, unbonded or undisclosed.

         (iii) Default interest rate payable at 18% per annum.

         Upon an Event of Default, the Payee shall provide written notice to the
Company declare the outstanding principal amount of the Note together with any
accrued interest thereon due and payable, and the same shall, unless such
default shall be cured within thirty (30) days after such notice, forthwith
become due and payable upon the expiration of such thirty (30) day period,
without presentment, demand, protest, or other notice of any kind, all of which
are expressly waived.

         It is expressly understood that this Note is solely a corporate
obligation of the Company and that any and all personal liability, either at
common law or in equity or by constitution or statute, of,

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and any and all such rights and claims against, every promoter, subscriber,
incorporator, shareholder, officer, or director, as such, are hereby expressly
waived and released by the holder hereof by the acceptance of this Note and as
part of the consideration for the issue hereof.

         This Note may be redeemed by the Company with Payee's consent, in whole
or in part, at any time, or in part from time to time, without penalty. This
Note, any payment of principal or interest due hereunder or any interest, legal
or beneficial, in this Note or any such payment may not be negotiated, assigned,
transferred, pledged or otherwise encumbered. The Company may deem and treat the
registered holder hereof as the absolute owner of this Note (whether or not this
Note shall be overdue and notwithstanding any notice of ownership or writing
hereon made by anyone other than the Company, for the purpose of receiving
payment hereof or thereof or on account hereof and for all other purposes) and
the Company shall not be affected by notice to the contrary.

         The Payee, at his sole discretion, has the right at any time to convert
the entire amount outstanding on the Note to the common stock of the Company at
$________ per share by giving notice to the Company of Payee's intent

         The Company will grant to the Payee a warrants for shares of common
stock as follows (IF APPLICABLE):

                 No. of Warrants              Exercise Price

         These warrants shall expire on ___________. Any shares issued pursuant
to this conversion and all shares underlying the warrants shall be issued with
the appropriate SEC Rule 144 legend indicating they are restricted shares. The
Company agrees to file for a registration with the SEC within ____________ from
the date of the Note.

         The Payee has been provided access to all of the Company's materials
relating to the business, finances and operations of the Company. Payee hereby
acknowledges its status as an accredited investor, and its advisors understand
that this subordinated debenture involves a significant degree of risk.

         IN WITNESS WHEREOF, this Note has been executed and delivered on the
date specified above by the duly authorized representative of the Company and
shall be construed in accordance with and governed by the laws of the State of
Florida.

                                  METROPOLITAN HEALTH NETWORKS, INC.

                                  By:
                                           ------------------------------
                                           David S. Gartner,
                                           solely in his capacity as Chief
                                           Financial Officer and not
                                           Individually<PAGE>

SPECIMEN STOCK CERTIFICATE

                                           Document is copied.

   NUMBER                                                          SHARES

                           On The Go Healthcare, Inc.

                    INCORPORATED UNDER THE LAWS OF DELAWARE

                                                               SEE REVERSE FOR
                                                            CERTAIN DEFINITIONS

                                  COMMON STOCK             CUSIP  68219M  10  5

                                   [SPECIMEN]
                                [NOT NEGOTIABLE]

This Certifies That:

is owner of:

FULLY PAID AND NON-ASSESSABLE SHARES OF COMMON STOCK OF $.0001PAR VALUE EACH OF
                          On The Go Healthcare, Inc.

transferrable on the books of the Corporation in person or by attorney upon
surrender of this certificate duly endorsed or assigned. This certificate and
the shares represented hereby are subject to the laws of the State of Delaware,
and to the Certificate of Incorporation and Bylaws of the Corporation, as now
or hereafter amended. This Certificate is not valid until countersigned by the
Transfer Agent.

         WITNESS the facsimile seal of the Corporation and the facsimile
signatures of its duly authorized officers.

DATED:                      COUNTERSIGNED:
                              INTERNATIONAL REGISTRAR AND TRANSFER AGENCY, INC.
                                         P.O. BOX 62405, BOULDER CITY, NV 89006
                                                                 TRANSFER AGENT
                            BY:

                                                           AUTHORIZED SIGNATURE

                                [CORPORATE SEAL]

        /s/ Carol Segal                             /s/ Stuart Turk
          SECRETARY                                       PRESIDENT

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         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        UNIF GIFT MIN ACT -       Custodian
TEN ENT - as tenants by the                               ---------------------
          entireties                                       (Cust)       (Minor)
JT TEN  - as joint tenants with                   under Uniform Gifts to Minors
          right of survivorship                         Act
          and not as tenants in                             -----------------
          common                                                       (State)

    Additional abbreviations may also be used though not in the above list.

     For Value Received, ___________ hereby sell, assign and transfer unto

PLEASE INSERT SOCIAL SECURITY OR OTHER
    IDENTIFYING NUMBER OF ASSIGNEE

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 (PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS, INCLUDING ZIP CODE, OF ASSIGNEE)

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                                                                         Shares
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of the stock represented by the within Certificate, and do hereby irrevocably
constitute and appoint

                                                                       Attorney
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to transfer the said stock on the books of the within named Corporation with
full power of substitution in the premises.

Dated _______________

                                    -------------------------------------------
                                  NOTICE: THE SIGNATURE TO THIS ASSIGNMENT MUST
                                   CORRESPOND WITH THE NAME AS WRITTEN UPON THE
                                   FACE OF THE CERTIFICATE IN EVERY PARTICULAR,
                                    WITHOUT ALTERATION ON OR ENLARGEMENT OR ANY
                                                             CHANGE WHATSOEVER.

THE CORPORATION WILL FURNISH TO ANY STOCKHOLDER, UPON REQUEST AND WITHOUT
CHARGE, A FULL STATEMENT OF THE DESIGNATIONS, RELATIVE RIGHTS, PREFERENCES AND
LIMITATIONS OF THE SHARES OF EACH CLASS AND SERIES AUTHORIZED TO BE ISSUED, SO
FAR AS THE SAME HAVE BEEN DETERMINED, AND OF THE AUTHORITY, IF ANY, OF THE
BOARD TO DIVIDE THE SHARES INTO CLASSES OR SERIES AND TO DETERMINE AND CHANGE
THE RELATIVE RIGHTS, PREFERENCES AND LIMITATIONS OF ANY CLASS OR SERIES. SUCH
REQUEST MAY BE MADE TO THE SECRETARY OF THE CORPORATION OR TO THE TRANSFER
AGENT NAMED ON THIS CERTIFICATE.
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THE SIGNATURE TO THE ASSIGNMENT MUST CORRESPOND WITH THE NAME AS WRITTEN UPON
THE FACE OF THE CERTIFICATE IN EVERY PARTICULAR, WITHOUT ALTERATION ON OR
ENLARGEMENT OR ANY CHANGE WHATSOEVER, AND MUST BE GUARANTEED BY A COMMERCIAL
BANK OR TRUST COMPANY OR A MEMBER FIRM OF A NATIONAL OR REGIONAL OR OTHER
RECOGNIZED STOCK EXCHANGE IN CONFORMANCE WITH A SIGNATURE GUARANTEE MEDALLION
PROGRAM.

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