Exhibit 21.1

Subsidiaries of Universal Compression Holdings, Inc.

|Beijing Universal Compression Technical Services Company Ltd. |  | China                 
|------------------------------------------------------------- |  | ----------------------
|BRL Universal Equipment 2001 A, L.P.                          |  | Delaware              
|Compression Services de Mexico, S.A. de C.V.                  |  | Mexico                
|Compressor Systems International, Inc.                        |  | Delaware              
|Energy Dynamics de Venezuela, C.A.                            |  | Venezuela             
|Enterra Compression Investment Company                        |  | Delaware              
|Oceanic Compression Services, Pty. Ltd.                       |  | Australia             
|Probalance Engenharia Ltda.                                   |  | Brazil                
|PT Universal Compression Indonesia                            |  | Indonesia             
|UC Canadian Partnership Holdings Company                      |  | Nova Scotia           
|UC Canadian Partnership Minority Holdings Company             |  | Nova Scotia           
|UCO Compression 2002 LLC                                      |  | Delaware              
|UCO Compression Holding, L.L.C.                               |  | Delaware              
|Universal Compression (Australia) Pty Ltd.                    |  | Australia             
|Universal Compression (Ontario), Ltd.                         |  | British Virgin Islands
|Universal Compression (Thailand), Ltd.                        |  | Thailand              
|Universal Compression Argentina, SA                           |  | Argentina             
|Universal Compression Bolivia LTDA                            |  | Bolivia               
|Universal Compression B.V.                                    |  | The Netherlands       
|Universal Compression Canada, Limited Partnership             |  | Nova Scotia           
|Universal Compression Canadian Holdings, Inc.                 |  | Delaware              
|Universal Compression de Mexico, S.A. de C.V.                 |  | Mexico                
|Universal Compression de Venezuela Unicom, C.A.               |  | Venezuela             
|Universal Compression del Peru, S.R.L.                        |  | Peru                  
|Universal Compression Finance Company, Ltd.                   |  | Barbados              
|Universal Compression Holdings Canada Company                 |  | Nova Scotia           
|Universal Compression International Holdings, S.L.U.          |  | Spain                 
|Universal Compression International, Inc.                     |  | Delaware              
|Universal Compression International, Ltd.                     |  | Cayman Island         
|Universal Compression LTDA                                    |  | Brazil                
|Universal Compression of Colombia, Ltd.                       |  | Cayman Island         
|Universal Compression Services de Venezuela, C.A.             |  | Venezuela             
|Universal Compression Services, LLC                           |  | Delaware              
|Universal Compression, Inc.                                   |  | Texas                 
|Uniwhale de Columbia E.U.                                     |  | Cayman Island         
|Uniwhale Ltd.                                                 |  | Cayman Island         

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