Source Code. The source code tells you how you get an item needed for maintenance, repair, or overhaul of an
end item/equipment. Explanations of source codes follow:
Stock items; use the applicable NSN to requisition/request items with these
source codes. They are authorized to the level indicated by the code entered in
the 3rd position of the SMR code.
Items coded PC are subject to deterioration.
Items with these codes are not to be requested/requisitioned individually. They
are part of a kit which is authorized to the maintenance level indicated in the 3rd
position of the SMR code. The complete kit must be requisitioned and applied.
MO-Made at unit/AVUM
Items with these codes are not to be requisitioned/requested individually. They
must be made from bulk material which is identified by the P/N in the DESCRIP-
MF-Made at DS/AVIM
TION AND USABLE ON CODE (UOC) column and listed in the bulk material
group work package of the RPSTL. If the item is authorized to you by the 3rd
MH-Made at GS level
position code of the SMR code, but the source code indicates it is made at
ML-Made at SRA
higher level, order the item from the higher level of maintenance.
MD-Made at depot
AO-Assembled by unit/
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
AF-Assembled by DS/
assembled at the level of maintenance indicated by the source code. If the 3rd
position of the SMR code authorizes you to replace the item, but the source
AH-Assembled by GS
code indicates the item is assembled at a higher level, order the item from the
higher level of maintenance.
AL-Assembled by SRA
AD-Assembled by depot
Do not requisition an "XA" coded item. Order the next higher assembly.(Refer to
If an item is not available from salvage, order it using the CAGEC and P/N.
Installation drawings, diagrams, instruction sheets, field service drawings; iden-
tified by manufacturer's P/N.
Item is not stocked. Order an XD-coded item through normal supply channels
using the CAGEC and P/N given, if no NSN is available.
Cannibalization or controlled exchange, when authorized, may be used as a
source of supply for items with the above source codes except for those items
source coded "XA" or those aircraft support items restricted by requirements of
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:
Third Position. The maintenance code entered in the third position tells you the lowest maintenance level autho-
rized to remove, replace, and use an item. The maintenance code entered in the third position will indicate
authorization to the following levels of maintenance: