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                                                                    EXHIBIT 4.1

[FACE OF CERTIFICATE]

NUMBER
U

SEE REVERSE FOR CERTAIN DEFINITIONS

HARBOR ACQUISITION CORPORATION

UNITS CONSISTING OF ONE SHARE OF COMMON STOCK AND TWO WARRANTS EACH TO PURCHASE
ONE SHARE OF COMMON STOCK

UNITS

CUSIP 41154X 20 6

This Certifies that
is the owner of
Units.

Each Unit ("Unit") consists of one (1) share of common stock, par value $.0001
per share ("Common Stock"), of Harbor Acquisition Corporation, a Delaware
corporation (the "Company"), and two warrants (the "Warrants"). Each Warrant
entitles the holder to purchase one (1) share of Common Stock for $5.00 per
share (subject to adjustment). Each Warrant will become exercisable on the later
of (i) the Company's completion of a merger, capital stock exchange, asset
acquisition or other similar business combination and (ii) , 2006, and will
expire unless exercised before 5:00 p.m., New York City Time, on , 2010, or
earlier upon redemption (the "Expiration Date"). The Common Stock and Warrants
comprising the Units represented by this certificate are not transferable
separately prior to , 2005, subject to earlier separation in the discretion of
Ferris, Baker Watts, Incorporated. The terms of the Warrants are governed by a
Warrant Agreement, dated as of , 2005, between the Company and Continental Stock
Transfer & Trust Company, as Warrant Agent, and are subject to the terms and
provisions contained therein, all of which terms and provisions the holder of
this certificate consents to by acceptance hereof. Copies of the Warrant
Agreement are on file at the office of the Warrant Agent at 17 Battery Place,
New York, New York 10004, and are available to any Warrant holder on written
request and without cost.

This certificate is not valid unless countersigned by the Transfer Agent and
Registrar of the Company.

Witness the facsimile seal of the Company and the facsimile signature of its
duly authorized officers.

By

/s/

SECRETARY

[SEAL]

/s/

CHAIRMAN

COUNTERSIGNED AND REGISTERED:
CONTINENTAL STOCK TRANSFER & TRUST COMPANY
TRANSFER AGENT AND REGISTRAR

BY

AUTHORIZED SIGNATURE

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[REVERSE OF CERTIFICATE]

Harbor Acquisition Corporation

The Corporation will furnish without charge to each stockholder who so requests,
a statement of the powers, designations, preferences and relative,
participating, optional or other special rights of each class of stock or series
thereof of the Corporation and the qualifications, limitations, or restrictions
of such preferences and/or rights.

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 right of survivorship and not as tenants in
common

UNIF GIFT MIN ACT - ....(Cust)....Custodian ....(Minor).... under Uniform Gifts
to Minors Act ....(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 (PLEASE
PRINT OR TYPEWRITE NAME AND ADDRESS, INCLUDING ZIP CODE, OF ASSIGNEE) Units
represented by the within Certificate, and do hereby irrevocably constitute and
appoint
Attorney to transfer the said Units 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
or enlargement or any change whatever.

Signature(s) Guaranteed:

THE SIGNATURE(S) MUST BE GUARANTEED BY AN ELIGIBLE GUARANTOR INSTITUTION (BANKS,
STOCKBROKERS, SAVINGS AND LOAN ASSOCIATIONS AND CREDIT UNIONS WITH MEMBERSHIP IN
AN APPROVED SIGNATURE GUARANTEE MEDALLION PROGRAM, PURSUANT TO S.E.C. RULE
17Ad-15).