tsql - Convert varchar to 3 (sometimes 4) chars in T-SQL -

I select the data from the database. The value is (the name of the field is ADR_KOMP_VL):

  4, 61a, 100, 12, 58, 123C, 6A, 5   
 Required  
  004, 061a, 100, 012, 3, 0, 1, 2, 3, 2, 3, 4, 0, 058, 123C, 006A, 005.  
 The rules are:  
 
 always 3 digits  
 no location  
 If the original value is less than three digits, So keep it in front of 0. (Length is 3)  
 If the original value has one letter, keep it in front of 0 (but length 4)   
 I have a "no space" portion This is:  
  Select REPLACE (ADR_KOMP_VL, '', '')    is the solution yet:  
 < Code> SELECT RIGHT ('000' + CONVERT (VARCHAR (4)), REPLACE (ADR_KOMP_VL, '', '')), 3)   
 but it only gives me the correct length , When my value is in the value  no  my problem is how to handle values ​​with a letter in them ??   
 
 
 You can use a case statement:  
  SELECT ('0000' + VCHAR (4), Replace (ADR_COMVVVL, '', '')), 4) Other rights ('000' + converter (VARCHAR) (4), REPLACE (ADR_KOMP_VL, '', '')), 3) end)