(1) Source Code. The source code tells you how to get an item needed for maintenance, repair or overhaul of an
end item/equipment. Explanations of source codes follows
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
3d position of the SMR code.
**Items coded PC are subject to deterioration
Items with these codes are not to be
is part of a kit, which is authorized to the maintenance category indicated in the 3d position of the SMR code.
The complete kit with the above source codes, except for those source must be requisitioned and applied.
MO-(Made at UMItems with these codes are not
to be requested/ requisitioned
MF-(Made at DS/ individually. They must be made from bulk material which is identified by the part number in the
DESCRIPTION AND USABLEON CODE OC) 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 if 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
UM/AVUM Level)to be requested/requisitioned individually. The parts that
make up the assembled item
DS/A VIM Level) 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 by
authorizes you to replace the
item, but the source code indi-
AD-(Assembled cates the item is assembled at a
bled at a higher level, order the item from the higher level of maintenance.
Do not requisition an XA
-coded Item. Order its next higher assembly. (Also, refer to the NOTE
If an "XB" item is not available from salvage order it using the CAGE and part number given
Installation drawing, diagram, instruction sheet field service drawing, that is identified by the
manufacturer's part number.
item is not stocked Order an "XD coded item through normal supply channels using the CAGE and part
number given, if no NSN is available.
NOTE: Cannibalization or controlled exchange, when authorized may be used as source of supply for items coded "XA"
or those aircraft support items restricted by requirements of AR 700-42.
(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 one of
the following levels of main-
Crew or operator maintenance done within unit or aviation unit maintenance
Unit maintenance or aviation unit category can remove, replace and use the item
Direct support or aviation intermediate level can remove, replace and use the item
General support level can remove, replace and use the item
Specialized repair activity can remove, replace and use the item.