EXHIBIT 21

DRS TECHNOLOGIES, INC.  SUBSIDIARIES OF THE COMPANY AS OF MARCH 31, 2005

|SUBSIDIARY                                    |  | STATE OR COUNTRY
OF FORMATION
|--------------------------------------------- |  | -----------------------------
|NAI Technologies, Inc                         |  | New York                     
|DRS Electronic Systems, Inc                   |  | Delaware                     
|DRS Technical Services, Inc                   |  | Delaware                     
|DRS Surveillance Support Systems, Inc         |  | Delaware                     
|DRS Technologies Canadian Capital Corporation |  | Canada (Nova Scotia)         
|DRS Technologies Capital Company, Inc         |  | Canada (Nova Scotia)         
|DRS Tactical Systems, Ltd                     |  | United Kingdom               
|DRS Data Systems (Europe) Ltd                 |  | United Kingdom               
|DRS Rugged Systems (Europe) Products Ltd      |  | United Kingdom               
|DRS Systems Management Corporation            |  | Delaware                     
|Laurel Technologies Partnership               |  | Delaware                     
|DRS Power & Control Technologies, Inc         |  | Delaware                     
|DRS Electric Power Technologies, Inc          |  | Delaware                     
|DRS Power Technology, Inc                     |  | Delaware                     
|Paravant Inc                                  |  | Florida                      
|DRS Tactical Systems, Inc                     |  | Florida                      
|DRS Engineering Development Labs, Inc         |  | Ohio                         
|DRS Signal Technologies, Inc                  |  | Ohio                         
|DRS Signal Recording Technologies, Inc        |  | Maryland                     
|DRS Optronics, Inc                            |  | Delaware                     
|DRS Sensors & Targeting Systems, Inc          |  | Delaware                     
|DRS FPA, Inc                                  |  | Delaware                     
|DRS Infrared Technologies, LP                 |  | Delaware                     
|DRS Unmanned Technologies, Inc                |  | Delaware                     
|DRS Data & Imaging Systems, Inc               |  | Delaware                     
|DRS Data & Imaging Systems Limited            |  | United Kingdom               
|DRS Hadland Ltd                               |  | United Kingdom               
|DRS Technologies Canada, Inc                  |  | Delaware                     
|DRS Technologies Canada Company               |  | Canada (Nova Scotia)         
|DRS Communications Company LLC                |  | Delaware                     
|MSSC Company                                  |  | Pennsylvania                 
|Tech-Sym Corporation                          |  | Nevada                       
|DRS Test & Energy Management, Inc             |  | Delaware                     
|DRS EW & Network Systems, Inc                 |  | Delaware                     
|DRS Signal Solutions, Inc                     |  | Delaware                     
|DRS Training & Control Systems, Inc           |  | Florida                      
|Integrated Defense Technologies, Inc.         |  | Delaware                     
|T-S Holding Corporation                       |  | Texas                        
|DRS EW & Network Systems (Canada) Limited     |  | Canada                       
|DRS International, Inc                        |  | Delaware                     
|DRS Systems, Inc                              |  | Delaware                     
|Night Vision Equipment Co., Inc.              |  | Delaware                     
|DRS Hadland Photonics GmbH                    |  | Germany                      

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