ARMY TM 9-6115-584-24P NAVY NAVFAC P-8-622-24P AIR FORCE T.O.  35C2-3-456-4 Source Explanation Code PA PB PC** Stocked items; use the applicable NSN to request/requisition items with these source codes. They are authorized to the category indicated by the code entered in the 3rd position of the SMR PD code. PE **NOTE: Items coded PC are subject to deterioration. PF PG KD Items with these codes are not to be requested/requisitioned individually.  They are part of a kit KF which is authorized to the maintenance category indicated in the 3rd position of the SMR code. The complete kit must be requisitioned and applied. KB MO (Made at Unit/AVUM Level) Items with these codes are not to be requested/requisitioned MF (Made DS/AVIM  Level) individually.  They must be made from bulk material Which is identified by the part number in the DESCRIPTION  and MH (Made at GS Level) USABLE ON CODE (UOC) column and listed in the Bulk ML (Made at Specialized Repair Material group of the repair parts list in this RPSTL.  If the item Activity (SRA)) is authorized to you by the 3rd position code of the SMR code, but the source code indicates it is made at a higher level, order MD (Made at Depot) the item from the higher level of maintenance. AO (Assembled by Unit/AVUM Items with these Codes arenot to be r-este  requisitioned Level) individually.  The parts that make up the assembled item must be AF   (Assembled by DS/AVIM requisitioned orfabricated and assembled at the level of mainte- Level) nance indicated by the source code.  If the3rd position code of the SMR code authorizes you to replace the item, but the source AH (Assembled by GS Category) code indicates the items are assembled at a higher level, order AL (Assembled by SRA) the item from the higher level of maintenance. AD (Assembled by Depot) XA Do not requisition "XA"-coded item.  Order its next higher assembly.  (Refer to the NOTE below.) XB If an "XB" item is not available from salvage, order it using the CAGEC and part number given. XC Installation drawing, diagram, instruction sheet, field service drawing, that is identified  manufacturer's part number. XD Item is not stocked.  Order an XD"-coded item through normal supply channels using the CAGEC and part number given, if no NSN is available. NOTE Cannibalization  or  controlled  exchange,  when  authorized,  may  be  used  as  a  source  of supply  for  items  with  the  above  source  codes,  except  for  those  source  coded  "XA"  or those aircraft support items restricted by requirements of AR 750-1. (2) Maintenance Code.  Maintenance codes tell you the level(s) of maintenance authorized to USE and REPAIR support items.  The maintenance codes are entered in the third and fourth positions of the SMR code as follows: (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. } } } } 2