SECTION I: INTRODUCTION
TM 9-2350-256-20
c. COLUMN 3, MAINTENANCE FUNCTION This lists the functions to be performed on the item listed in column 2. (For
detailed explanation of these functions, see paragraph B-2.)
d. COLUMN 4, MAINTENANCE LEVEL This specifies each level of maintenance authorized to perform each function
listed in column 3 by indicating work-time required (expressed as man-hours in whole hours or decimals) in the
appropriate subcolumn. This work-time figure represents the active time required to perform that maintenance function at
the indicated level of maintenance. If the number or complexity of the tasks within the listed maintenance function vary at
different maintenance levels, appropriate work-time figures are to be shown for each level. The work-time figure
represents the average time required to restore an item (assembly, subassembly, component, module, end item, or
system) to a serviceable condition under typical field operating conditions. This time includes preparation time (including
any necessary disassembly/assembly time), fault location/troubleshooting time, and quality assurance time in addition to
the time required to perform the specific tasks identified for the maintenance functions authorized in the MAC. The
symbol designations for the various maintenance levels are as follows:
C ..................................Operator/Crew Maintenance
O ..................................Unit Maintenance
F...................................Direct Support Maintenance
L ...................................Specialized Repair Activity (SRA)5
H ..................................General Support Maintenance
D ..................................Depot Maintenance
e. COLUMN 5, TOOLS AND TEST EQUIPMENT REFERENCE CODE This specifies, by code, those common tools
sets (not individual tools), common Test, Measurement, and Diagnostic Equipment (TMDE), and special tools, special
TMDE, and special support equipment required to perform the designated function. Codes are keyed to tools and test
equipment in Section III.
f. COLUMN 6, REMARKS When applicable, this contains a letter code, in alphabetical order.
B4 EXPLANATION OF COLUMNS IN TOOLS AND TEST EQUIPMENT, SECTION III
a. COLUMN 1, REFERENCE CODE This is correlated with the code used in the MAC, Section II, column 5.
b. COLUMN 2, MAINTENANCE LEVEL This is the lowest level of maintenance authorized to use the tool or test
equipment.
c. COLUMN 3, NOMENCLATURE This is the name or identification of the tools or test equipment.
d. COLUMN 4, NATIONAL STOCK NUMBER (NSN) This is assigned to the tool or test equipment; use it to request or
requisition the item.
e. COLUMN 5, TOOL NUMBER This is the manufacturer's part number, model number, or type number.
5 This maintenance level is not included in Section II, column 4 of the MAC. Functions to this level of maintenance
are identified by a work-time figure in the "H" column of Section II, column 4 and an associated referenced code
is used in the "Remarks" column, column 6.
B-3
