Operating instructions
TM 11574A-OI
4-4
SECTION III
III. DEFINITIONS AND APPLICATION OF SOURCE, MAINTENANCE, RECOVERABILITY
CODES (SMRC)
4-3. Source Codes
Source codes are assigned to support items and indicate the manner of acquiring the item for
maintenance or overhaul of end items. Source codes are entered in the first and second position
of the SMR code.
a. SERIES A: ASSEMBLE, COMPLETE ASSEMBLY NOT STOCKED
1. Code “A” entered in the first position of the source code applies to items that are not procured
as assemblies but are assembled within the Marine Corps prior to installation. The code
entered in the second position designates the lowest echelon authorized to assemble the
item. All the parts used in the assembly will be “P” coded.
Code
Application/Explanation
AO
Assemble at organizational maintenance level 2
nd
echelon.
AF
Assemble at field maintenance level 3
rd
echelon.
AH
Assemble at field maintenance level 4
th
echelon.
AD
Assemble at depot maintenance 5
th
echelon.
b. SERIES K: ITEMS OF A KIT, NOT PURCHASED SEPARATELY
KD An item of depot overhaul/repair kit and not purchased separately. Depot
kit defined as a kit that provides items required at the time of
overhaul or repair.
KF An item of a maintenance kit and not purchased separately. Maintenance
kit defined as a kit that provides an item that can be replaced
at organizational or intermediate levels of maintenance
KB Items included in both a depot overhaul/repair kit and a
maintenance kit.
c. SERIES M: MANUFACTURE, PARTS NOT PRODUCED
Code “M” entered in the first position of the source code applies to items that are not
procured but are capable of being fabricated or manufactured within the Marine Corps.
These items have relatively low usage and will generally be fabricated or manufactured only
as required for immediate repair or replacement. The code entered in the second position
designates the lowest echelon authorized to manufacture or fabricate the item. Units will
requisition the bulk materiel under the NSNs and the quantities indicated to effect the
fabrication or manufacture of the item.
MO Manufacture or fabricate at organizational maintenance level 2
nd
echelon.
MF Manufacture or fabricate at field maintenance level 3
rd
echelon.
MH Manufacture or fabricate at field maintenance level 4
th
echelon.
MD Manufacture or fabricate at field maintenance level 5
th