TM 10-3930-665-13&P MO -   Made at Org/AVUM category MF -    Made at DS/AVIM category MH -   Made at GS category ML - Made at Specialized Repair Activity (SRA) MD -   Made at Depot AO -    Assembled by Org/AVUM category AF - Assembled by DS/AVIM category AH - Assembled by GS category AL - Assembled by SRA AD - Assembled by Depot Items with these codes are not to  be  requested/requisitioned  individually. They  must  be  made  from  bulk  material  which  is  identified  by  the  part number  in  the  DESCRIPTION  AND  USABLE  ON  CODE  (UOC)  column and listed in the Bulk Material group of the repair parts list in this RPSTL. If the item is authorized to you by the 3d position code of the SMR code, but the source code indicates it is made at a higher level,  order  the  item from the higher level of maintenance. Items with these codes are not to  be  requested/requisitioned  individually. The  parts  that  make  up  the  assembled  item  must  be  requisitioned  or fabricated  and  assembled  at  the  level  of  maintenance  indicated  by  the source code.  If the 3d position code of the SMR code authorizes  you  to replace the item, but the source code indicates the item is assembled at a higher level, order the item from the higher level of maintenance. XA  - Do not requisition an "XA"-coded item.  Order its next higher assembly.  (Also, 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  by  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. 3