Exhibit 4.1


 


	
  NUMBER

  	
   

  	
   

  	
   

  	
  UNITS

  
	
  U-

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
  SEE REVERSE

  FOR CERTAIN

  DEFINITIONS

  	
   

  	
  FEDERAL SERVICES
  ACQUISITION CORPORATION

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
  CUSIP

  



 


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


 


 


	
  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 Federal Services
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, stock
purchase or other similar business combination or (ii)                         ,
2006 and will expire unless exercised before 5:00 p.m., New York City
Time, on                   ,
2009, 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 CRT Capital Group
LLC.  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

  	
   

  	
  Federal Services Acquisition

  Corporation

  	
   

  	
   

  
	
   

  	
   

  	
  CORPORATE

  	
   

  	
   

  
	
   

  	
   

  	
  DELAWARE

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
  SEAL

  	
   

  	
   

  	
   

  
	
  Chairman of the
  Board

  	
   

  	
   

  	
  2005

  	
   

  	
  Secretary

  	
   

  



 





















 


Federal Services Acquisition Corporation


 


The Company 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 Company 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

  	
  UNIF GIFT MIN
  ACT -

  	
  Custodian

  
	
  TEN ENT -

  	
  as tenants by
  the entireties

  	
   

  	
  (Cust)

  	
  (Minor)

  
	
  JT TEN -

  	
  as joint tenants
  with right

  	
  under Uniform
  Gifts to Minors Act

  
	
   

  	
  of survivorship
  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


 


 


(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 Company
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.

  



 


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Signature(s) Guaranteed:


 


 


	
   

  	
   

  
	
  THE SIGNATURE(S)
  SHOULD 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).

  	
   

  



 


 


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