TM 10-4610-234-23P (a) The maintenance code entered in the third position tells you the lowest maintenance level authorized to remove, replace, and use an item.  The maintenance code entered in the third position will indicate authorization to the following levels of maintenance. Maintenance Application/Explanation Code C - Crew or operator maintenance done within unit/AVUM maintenance. O - Unit level/AVUM maintenance can remove, replace, and use the item. F - Direct support/AVIM maintenance can remove, replace, and use the item. H - General support maintenance can remove, replace, and use the item. L - Specialized repair activity can remove, replace, and use the item. D - Depot can remove, replace, and use the item. (b) The maintenance code entered in the fourth position tells whether or no the item is to be repaired and identifies  the  lowest  maintenance  level  with  the  capability  to  do  complete  repair  (i.e.,  perform  all  authorized  repair functions.) NOTE Some  limited  repair  may  be  done  on  an  item  at  a  lower  level  of  maintenance,  if authorized by the Maintenance Allocation Chart and SMR codes. Maintenance Application/Explanation Code O - Unit/AVUM is the lowest level that can do complete repair of the item. F - Direct support/AVIM is the lowest level that can do complete repair of the item. H - General Support is the lowest level that can do complete repair of the item. L - Specialized repair activity is the lowest level that can do complete repair of the item. D - Depot is the lowest level that can do complete repair of the item. Z - Nonreparable.  No repair is authorized. B - No repair is authorized.  No parts or special tools are authorized for the maintenance of a "B" coded item.  However, the item may be reconditioned by adjusting, lubricating, etc., at the user level. (3) Recoverability  Code.    Recoverability  codes  are  assigned  to  items  to  indicate  the  disposition  action  on unserviceable items.  The recoverability code is entered in the fifth position of the SMR Code as follows: Recoverability Application/Explanation Codes Z - Nonreparable   item.      When   unserviceable,   condemn   and   dispose   of   the   item   at   the   level   of maintenance shown in 3d position of SMR Code. O - Reparable  item.    When  not  economically  repairable,  condemn  and  dispose  of  the  item  at  unit  or AVUM level. F - Reparable  item.    When  uneconomically  reparable,  condemn  and  dispose  of  the  item  at  the  direct support or AVIM level. H - Reparable item.  When uneconomically  reparable,  condemn  and  dispose  of  the  item  at  the  general support level. D - Reparable  item.    When  beyond  lower  level  repair  capability,  return  to  depot.    Condemnation  and disposal of item not authorized below depot level. 3