EXHIBIT 4.1



GRUPO IMSA, S.A. DE C.V.



|    |  | Name                               |  | Jurisdiction ofIncorporation |  | Doing Business as                  
|--- |  | ---------------------------------- |  | ---------------------------- |  | -----------------------------------
|1   |  | IMSA ACERO, S.A. DE C.V.           |  | Mexico                       |  |                                   
|    |  |                                    | 
|1-1 |  | IMSA-MEX, S.A. DE C.V.             |  | Mexico                       |  | Imsa-Mex                           
|    |  |                                    | 
|1-2 |  | INDUSTRIA GALVANIZADORA, S.A.      |  | Guatemala                    |  | Ingasa                             
|    |  |                                    | 
|1-3 |  | IMSA STEEL, CORP.                  |  | U.S.A.                       |  | Steelscape Imsa                    
|    |  |                                    | 
|2   |  | ENERMEX, S.A. DE C.V.              |  | Mexico                       |  |                                   
|    |  |                                    | 
|2-1 |  | ENERTEC MEXICO, S. DE R.L. DE C.V. |  | Mexico                       |  | Enertec México                     
|    |  |                                    | 
|2-2 |  | GES AMERICA, L.L.C.                |  | Delaware, U.S.A.             |  | GES America                        
|    |  |                                    | 
|2-3 |  | ENERTEC DO BRASIL, LTDA.           |  | Brazil                       |  | Enertec do Brasil                  
|    |  |                                    | 
|2-4 |  | ENERTEC ARGENTINA, S.A.            |  | Argentina                    |  | Enertec Argentina                  
|    |  |                                    | 
|2-5 |  | ENERTEC VENEZUELA, S.R.L.          |  | Venezuela                    |  | Enertec Venezuela                  
|    |  |                                    | 
|3   |  | IMSALUM, S.A. DE C.V.              |  | Mexico                       |  |                                   
|    |  |                                    | 
|3-1 |  | CUPRUM, S.A. DE C.V.               |  | Mexcio                       |  | Cuprum                             
|    |  |                                    | 
|3-2 |  | VENTANAS CUPRUM, S.A. DE C.V.      |  | Mexico                       |  | Ventanas Cuprum                    
|    |  |                                    | 
|3-3 |  | LOUISVILLE LADDER GROUP, LLC       |  | Delaware, U.S.A.             |  | Louisville Ladder                  
|    |  |                                    | 
|3-4 |  | ESCALERAS, S. DE R.L. DE C.V.      |  | Mexico                       |  | Escaleras                          
|    |  |                                    | 
|3-5 |  | TIENDAS ALUTODO, S.A. DE C.V.      |  | Mexico                       |  | Teindas Alutodo                    
|    |  |                                    | 
|4   |  | IMSATEC, S.A. DE C.V.              |  | Mexico                       |  |                                   
|    |  |                                    | 
|4-1 |  | EMPRESAS STABILIT, S.A. DE C.V.    |  | Mexico                       |  | Stabilit; Glasteel;Graham; Resolite
|    |  |                                    | 
|4-2 |  | IMSA ITW, S.A. DE C.V.             |  | Mexico                       |  | IMSA Signode;IMSA Paslode;STAHL    
|    |  |                                    | 
|4-3 |  | FORJAS METALICAS, S.A. DE C.V.     |  | Mexico                       |  | Formet                             
|    |  |                                    | 
|4-4 |  | MULTYPANEL, S.A. DE C.V.           |  | Mexico                       |  | Multypanel                         



---

|4-5  |  | METL-SPAN, CORP.                   |  | Texas, U.S.A.      |  | Metl Span                                        
|---- |  | ---------------------------------- |  | ------------------ |  | -------------------------------------------------
|     |  |                                    | 
|4-6  |  | GRUPO IMSA CHILE, S.A.             |  | Chile              |  | Grupo IMSA Chile;Varco Pruden Chile;Tecnosteel   
|     |  |                                    | 
|4-7  |  | BAYER IMSA, S.A. DE C.V.           |  | Mexico             |  | Bayer-IMSA                                       
|     |  |                                    | 
|4-8  |  | VALMONT FORMET, S. DE R.L. DE C.V. |  | Mexico             |  | Valmont Formet                                   
|     |  |                                    | 
|4-9  |  | VARCO PRUDEN HOLDING, INC.         |  | Delaware, U.S.A.   |  | Varco Pruden Buildings;United Panel; ASC Profiles
|     |  |                                    | 
|4-10 |  | IMSA VARCO PRUDEN, S.A. DE C.V.    |  | Mexico             |  | IMSA Varco Pruden                                
|     |  |                                    | 
|4-11 |  | ASC PROFILES INC.                  |  | Washington, U.S.A. |  | ASC Profiles