TM 5-6115-590-20P AD Item to be assembled at depot maintenance level. XA Item is not procured or stocked because the requirements for the item will result in the replacement of the next higher assembly. XB Item is not procured or stocked.  If not available through salvage, requisition. XD A support item that is not stocked.  When required, item will be procured through normal supply channels. NOTE Cannibalization or salvage may be used as   a   source   of   supply   for   any   items source coded above except those coded XA or XD. (2)  Maintenance  Code.    Maintenance  codes  are assigned to indicate the levels of maintenance authorized to use and repair support items.  The maintenance codes are entered in the third and fourth position of the Uniform SMR Code format as follows: (a)    The   maintenance   code   entered   in   the   third position    will    indicate    the    lowest    maintenance    level authorized to remove, replace, and use the support item. The  maintenance  code  entered  in  the  third  position  will indicate one of the following levels of maintenance. Code Application/Explanation C Crew or operator maintenance performed within organizational maintenance. O Support item is removed, replaced, used at the organizational level. (b)  The   maintenance   code   entered   in   the   fourth position  indicates  whether  the  item  is  to  be  repaired  and identifies the lowest maintenance level with the capability to perform complete repair (i.e., all authorized maintenance functions).  This position will contain one of the following maintenance codes: Code Application/Explanation O The lowest maintenance level capable of complete repair of the support item is the organizational level. F The lowest maintenance level capable of complete repair of the support item is the direct support level. H The lowest maintenance level capable of complete repair of the support item is the general support level. D The lowest maintenance level capable of complete repair of the support item is the depot level. L Repair restricted to designated specialized repair activity. Z Nonreparable.  No repair is authorized. B No repair is authorized.  The item may be reconditioned by adjusting, lubricating, etc.  , at the user level.  No parts or special tools are procured for the maintenance of this item. (3)  Recoverability  Codes.    Recoverability  codes are  assigned  to  support  items  to  indicate  the  disposition action on unserviceable items.  The recoverability code is entered  in  the  fifth  position  of  the  Uniform  SMR  Code format as follows:  Recoverability Codes Definition Z Nonreparable item.  When unserviceable, condemn and dispose at the level indicated in Position 3. O Reparable item.  When  uneconomically reparable, condemn and dispose at organizational level. F Reparable item.  When  uneconomically reparable, condemn and dispose at the direct support level. H Reparable item.  When  uneconomically reparable, condemn and dispose at the general support level. D Reparable item.  When beyond lower level repair capability, return to depot.  Condemnation and disposal not authorized below depot level. L Reparable item.  Repair, condemnation, and disposal not authorized below depot/specialized repair activity level. A Item requires special handling or condemnation procedures because of specific reasons (i.  e.  , precious metal content, high dollar value, critical material or hazardous material).  Refer to appropriate manuals/directives for specific instructions. 2