Exhibit 10.15.4


 


October 19, 2005


 


CRT Capital Group LLC


262 Harbor Drive


Stanford, CT 06902


 


Re:          Federal Services Acquisition
Corporation


 


Ladies and Gentlemen:


 


This letter agreement
(this “Warrant Purchase Letter”) is being delivered to you in connection with
the Registration Statement on Form S-1 (File No. 333-124638) (as may
be amended and supplemented from time to time, the “Registration Statement”)
that was initially filed by Federal Services Acquisition Corporation, a
Delaware corporation (the “Company”), with the Securities and Exchange
Commission (the “SEC”) on May 4, 2005, which relates to an underwritten
initial public offering (the “IPO”) of the Company’s units (the “Units”), each
comprised of one share of the Company’s common stock, par value $0.0001 per
share (the “Common Stock”), and two warrants, each of which are exercisable for
one share of Common Stock (each, a “Warrant”).  Capitalized terms used but
not otherwise defined herein shall have their respective meanings set forth on
Schedule 1 hereto.


 


For good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged,
the undersigned hereby agrees as follows:


 


(1) Prior to the
execution of the underwriting agreement between the Company and CRT Capital
Group LLC (the “Underwriter”), the undersigned shall duly execute and deliver
an irrevocable order to purchase Warrants (the “Order”) to the Underwriter, in
the form attached hereto as Schedule 2, with such terms and conditions as
are consistent with the terms and conditions set forth in the Registration
Statement as of the Effective Date and the terms and conditions set forth
herein.


 


(2) The undersigned
shall, within the forty (40) trading day period beginning sixty (60) days after
the end of the “restricted period” under Regulation M as determined by the
Underwriter, purchase for the undersigned’s own account up to $2,000,000 of
Warrants at market prices not to exceed $0.65 per Warrant.


 


(3) The undersigned
shall not offer, pledge, sell, transfer or otherwise dispose of, either
directly or indirectly, any Warrants purchased pursuant to this Warrant
Purchase Letter or the Order until after the Business Combination Date.


 


This Warrant Purchase
Letter shall be binding on the undersigned and his respective successors and assigns.


 

















 


This Warrant Purchase
Letter shall be governed by and interpreted and construed in accordance with
the laws of the State of New York applicable to contracts formed and to be
performed entirely within the State of New York, without regard to the
conflicts of law provisions thereof to the extent such principles or
rules would require or permit the application of the laws of another
jurisdiction.


 


No term or provision of
this Warrant Purchase Letter may be amended, changed, waived, altered or modified
except by written instrument executed and delivered by the party against whom
such amendment, change, waiver, alteration or modification is to be enforced.


 


	
   

  	
  Very truly yours,

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
    /s/
  JOEL R. JACKS

  	
   

  
	
   

  	
  Joel
  R. Jacks, on behalf of

  
	
   

  	
  FSAC Partners, LLC

  
	
   

  	
   

  
	
  Accepted and agreed as
  of the date hereof:

  	
   

  
	
  CRT CAPITAL GROUP LLC

  	
   

  
	
   

  	
   

  
	
   

  	
   

  
	
  By: 

  	
  /s/ ERIC SEAL

  	
   

  	
   

  
	
  Name: Eric Seal

  	
   

  
	
  Title: Vice President

  	
   

  
					



 


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SCHEDULE 1


 


Supplemental Common Definitions


 


UNLESS
THE CONTEXT SHALL OTHERWISE REQUIRE, THE FOLLOWING TERMS SHALL HAVE THE
FOLLOWING RESPECTIVE MEANINGS FOR ALL PURPOSES, AND THE FOLLOWING DEFINITIONS
ARE EQUALLY APPLICABLE TO BOTH THE SINGULAR AND THE PLURAL FORMS AND THE
FEMININE, MASCULINE AND NEUTER FORMS OF THE TERMS DEFINED.


 


“Business Combination”
shall mean the acquisition by the Company, whether by merger, capital stock
exchange, asset acquisition, stock purchase or other similar business
combination, of one operating business in the federal services and defense
industries, which has a fair market value (as calculated in accordance with the
Company’s Amended and Restated Certificate of Incorporation) equal to at least
80% of the Company’s net assets at the time of such merger, capital stock
exchange, asset acquisition, stock purchase or other similar business
combination.


 


“Business Combination
Date” shall mean the date upon which a Business Combination is consummated.


 


“Effective Date” shall
mean the date upon which the Registration Statement is declared effective under
the Securities Act of 1933, as amended, by the SEC.


 


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SCHEDULE 2


 


October
    , 2005


 


CRT
Capital Group LLC


262
Harbor Drive


Stamford,
CT 06902


 


RE:          Federal Services Acquisition Corporation


 


Gentlemen:


 


This letter, delivered in
accordance with the Warrant Purchase Letter, dated October    ,
2005, between CRT Capital Group LLC (the “Underwriter”) and the undersigned
(the “Warrant Purchase Letter”), confirms the agreement thereon of the undersigned
to purchase (the “Purchase Commitment”) warrants (the “Warrants”) of Federal
Services Acquisition Corporation (the “Company”) that are included in the units
being sold in the Company’s initial public offering pursuant to the Company’s
registration statement on Form S-1 (File No. 333-124638), as amended
and supplemented from time to time.  The Purchase Commitment is subject to
the terms and conditions set forth herein.


 


The undersigned agrees
that this letter agreement constitutes an irrevocable order (the “Order”) for
the Underwriter to purchase for the undersigned’s account, within the forty
(40) trading days beginning sixty (60) days after the end of the “restricted
period” under Regulation M as determined by the Underwriter (such date, the “Commitment
Date”), up to $2,000,000 of Warrants at market prices not to exceed $0.65 per
Warrant.  The Underwriter (or such other broker-dealer(s) as the
Underwriter may assign the order to) agrees to fill such order in such amounts
and at such times as it may determine, in its sole discretion, during the forty
(40) trading days commencing on the Commitment Date.  The Underwriter
further agrees that it will not charge the undersigned or any Designee (as
defined below) any fees and/or commissions with respect to any purchase
pursuant to the Warrant Purchase Letter or the Order.


 


The undersigned may
notify the Underwriter that all or part of the Order will be fulfilled by an
affiliate of the undersigned (or another person or entity identified to the
Underwriter by the undersigned (each a “Designee”)) who (or which) has an
account at the Underwriter and, in such event, the Underwriter will make such
purchase on behalf of said affiliate or Designee; provided, however,
that the undersigned hereby agrees to make payment of the purchase price of
such purchase in the event that the affiliate or Designee fails to make such
payment; provided  further, that any such Designee has executed an
agreement, satisfactory to the Underwriter, pursuant to which such Designee
agrees not to offer, pledge, sell, transfer or otherwise dispose of, either


 


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directly or indirectly,
any Warrants purchased pursuant to the Warrant Purchase Letter or the Order
until after the Business Combination Date (as defined in the Warrant Purchase
Letter).


 


This letter agreement
shall be binding on the undersigned and his respective heirs, successors and
assigns.


 


This letter agreement
shall be governed by and interpreted and construed in accordance with the laws
of the State of New York applicable to contracts formed and to be performed
entirely within the State of New York, without regard to the conflicts of law
provisions thereof to the extent such principles or rules would require or
permit the application of the laws of another jurisdiction.


 


No term or provision of
this letter agreement may be amended, changed, waived, altered or modified
except by written instrument executed and delivered by the party against whom
such amendment, change, waiver, alteration or modification is to be enforced.


 


	
   

  	
  Very
  truly yours,

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  Joel
  R. Jacks, on behalf of

  
	
   

  	
  FSAC Partners, LLC

  



 


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