Exhibit 21

SUBSIDIARIES OF THE COMPANY



|                                                            |  |                                   
|----------------------------------------------------------- |  | ----------------------------------
|Name                                                        |  | State or Province
of Incorporation
|                                                            | 
|SenDEC Corp.                                                |  | New York                          
|                                                            | 
|API Cryptek Inc. d/b/a ION Networks                         |  | Delaware                          
|                                                            | 
|API Electronics Group Corp.                                 |  | Ontario                           
|                                                            | 
|API Electronics, Inc.                                       |  | Delaware                          
|                                                            | 
|API Nanofabrication and Research Corporation d/b/a NanoOpto |  | Delaware                          
|                                                            | 
|API Nanotronics Holdings Corp.                              |  | Ontario                           
|                                                            | 
|API Nanotronics Sub, Inc.                                   |  | Ontario                           
|                                                            | 
|API Systems, Inc.                                           |  | Delaware                          
|                                                            | 
|API Defense, Inc.                                           |  | Delaware                          
|                                                            | 
|API Defense USA, Inc.                                       |  | Delaware                          
|                                                            | 
|Emcon USA, Inc. (f/k/a API Secure Technologies Inc.)        |  | Delaware                          
|                                                            | 
|Cryptek Holdco UK Limited                                   |  | United Kingdom                    
|                                                            | 
|Emcon2007 Holdco Inc.                                       |  | Canada                            
|                                                            | 
|Emcon Emanation Control Ltd.                                |  | Canada                            
|                                                            | 
|Filtran Inc.                                                |  | New York                          
|                                                            | 
|Filtran Limited                                             |  | Ontario                           
|                                                            | 
|Keytronics Inc.                                             |  | New York                          
|                                                            | 
|National Hybrid, Inc.                                       |  | New York                          
|                                                            | 
|Pace Technology, Inc.                                       |  | Florida                           
|                                                            | 
|Secure Computer Systems Ltd.                                |  | United Kingdom                    
|                                                            | 
|Secure Systems & Technologies, Ltd.                         |  | United Kingdom                    
|                                                            | 
|Secure Systems Production Limited                           |  | United Kingdom                    
|                                                            | 
|TM Systems II, Inc.                                         |  | Delaware                          
|                                                            | 
|Spectrum Control, Inc.                                      |  | Pennsylvania                      



---

|                                                 |  |                          
|------------------------------------------------ |  | -------------------------
|                                                 | 
|Spectrum Control, Inc.                           |  | Delaware                 
|                                                 | 
|Spectrum Engineering International, Inc.         |  | Delaware                 
|                                                 | 
|Spectrum Control Technology, Inc.                |  | Delaware                 
|                                                 | 
|Spectrum FSY Microwave, Inc.                     |  | Maryland                 
|                                                 | 
|Spectrum SEI Microwave, Inc.                     |  | Delaware                 
|                                                 | 
|Spectrum Microwave, Inc.                         |  | Delaware                 
|                                                 | 
|Spectrum Sensors and Controls, Inc.              |  | California               
|                                                 | 
|Spectrum Sensors and Controls, Inc.              |  | Pennsylvania             
|                                                 | 
|Spectrum Control GmbH                            |  | Germany                  
|                                                 | 
|Spectrum Control de Mexico                       |  | Mexico                   
|                                                 | 
|Spectrum Control (Hong Kong) Limited             |  | Hong Kong                
|                                                 | 
|Spectrum Control Electronics (Dongguan) Co. LTD. |  | Peoples Republic of China
|                                                 | 
|Spectrum Sensors and Controls, Inc.              |  | Ohio