Exhibit 21

AAF-MCQUAY INC.  SUBSIDIARIES AND AFFILIATES

|AMG Holdings B.V. (The Netherlands)                             |  | * McQuay Szanyó Klimatechnika Kft. (Hungary) 
|--------------------------------------------------------------- |  | ---------------------------------------------
|AMG Holdings N.V. (The Netherlands)                             |  | * AAF Saudi Arabia Limited (Saudi Arabia)    
|AAF-McQuay Group Inc. (Delaware)                                |  | * Kirloskar AAF Ltd. (India)                 
|AAF-McQuay Inc. (Delaware)                                      |  | * Kirloskar-McQuay Pvt. Ltd. (India)         
|AAF-McQuay Holdings Inc. (Texas)                                |  | * Equipos McQuay, S.A. de C.V. (Mexico)      
|AAF-McQuay International Inc. (Delaware)                        |  | * Janitrol de Mexico, S.A. de C.V. (Mexico)  
|AAF-McQuay Canada Inc. (Canada)                                 |  | * Aerofil Filtracion de Aire C.V. (Venezuela)
|AAF-McQuay Export Inc. (Barbados)                               |  | * McQuay Caribe, Inc. (Puerto Rico)          
|American Air Filter Company, Inc. (Delaware)                    |  | * American Air Filter Sdn Bhd (Malaysia)     
|McQuay-Perfex Export Co. (Minnesota)                            |  | * McQuay Mediterranean LLC (Delaware)        
|McQuay-TPC Corp. (Delaware)                                     |  |                                              
|AAF-McQuay Netherlands B.V. (The Netherlands)                   |  |                                              
|AAF-International B.V. (The Netherlands)                        |  |                                              
|AAF Luftreinigungssysteme Gesellschaft m.b.H (Austria)          |  |                                              
|AAF-SA (Belgium)                                                |  |                                              
|AAF-SA (France)                                                 |  |                                              
|AAF-McQuay Holding France (France)                              |  |                                              
|AAF-McQuay France (France)                                      |  |                                              
|AAF-Lufttechnik GmbH (Germany)                                  |  |                                              
|Beth Lufttechnik GmbH (Germany)                                 |  |                                              
|AAF Environmental Control E.P.E. (Greece)                       |  |                                              
|AAF S.r.l. (Italy)                                              |  |                                              
|AAF Italia S.r.l., f/k/a McQuay Europa S.r.l. (Italy)           |  |                                              
|McQuay Italia S.p.A. (Italy)                                    |  |                                              
|AAF, S.A. (Spain)                                               |  |                                              
|AAF McQuay UK Limited (United Kingdom)                          |  |                                              
|AAF-Limited (United Kingdom)                                    |  |                                              
|McQuay (UK) Limited (United Kingdom)                            |  |                                              
|Air Filters Limited (United Kingdom)                            |  |                                              
|J & E Hall Limited (United Kingdom)                             |  |                                              
|Coulstock & Place Engineering Co. Limited (United Kingdom)     
|Balmsound Limited (United Kingdom)                              |  |                                              
|AAF Hava Filtreleri ve Ticaret A.S. (Turkey)                    |  |                                              
|AAF Asia Pte Limited (Singapore)                                |  |                                              
|AAF, S. de R.L. de C.V. (Mexico)                                |  |                                              
|Purificacion de Aire Venezolana, C.A. (Venezuela)               |  |                                              
|American Air Filter Brasil Ltda.(Brazil)                        |  |                                              
|McQuay - Ar Condicionado Brasil Ltda (Brazil)                   |  |                                              
|McQuay Latin America, L.C. (Florida)                            |  |                                              
|McQuay de Venezuela C.A. (Venezuela)                            |  |                                              
|McQuay España S.A. (Spain)                                      |  |                                              
|* McQuay New York, LLC (New York)                               |  |                                              
|* AAF-McQuay L.L.C. (United Arab Emirates - Dubai)              |  |                                              
|* McQuayService S.r.l. (Italy)                                  |  |                                              
|* McQuay Beirut (Offshore), Inc. S.A.L. (Lebanon)               |  |                                              
|* TriState HVAC Equipment, LLP (Pennsylvania)                   |  |                                              
|* McQuay of Georgia LLP (Georgia)                               |  |                                              
|* McQuay Southeast Service, LLC (Georgia)                       |  |                                              
|* McQuay Southeast Supply, LLC (Georgia)                        |  |                                              
|* Applied Control Systems, LLC (Georgia)                        |  |                                              
|* AF Technology, Ltd., formerly AAF Korea Company, Ltd. (Korea)
|* McQuay Hellas Air-Conditioning and Refrigeration SA (Greece) 

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