TM 55-4920-431-23P
e. PART NUMBER. Indicates the primary number used by the manufacturer (individual, company, firm,
corporation, or Government activity), which controls the design and characteristics of the item by means of its
engineering drawings, specifications, standards and inspection requirements to identify an item or range of items.
NOTE: When a stock-numbered item is requisitioned, the item received may have a different part number than
the part being replaced.
f. Description. Indicates the Federal item name and, if required, a minimum description to identify the item.
Items that are included in kits and sets are listed below the name of the kit or set with the quantity of each item in the kit
or set indicated in the quantity incorporated in unit column. When the part to be used differs between serial numbers of
the same model, the effective serial numbers are shown as the last line of the description. In the Special Tools List, the
initial basis of issue (B01) appears at the last line in the entry for each special tool, special TMDE, and other special -
support equipment. When density of equipments supported exceeds density spread indicated in the basis of issue, the
total authorization is increased accordingly.
g. Unit of Measure (U/M). Indicates the standard of the basic quantity of the listed item as used in performing
the actual maintenance function. This measure is expressed by a two-character alphabetical abbreviation (e.g., ea, in,
pr, etc). When the unit of measure differs from the unit of issue, the lowest unit of issue that will satisfy the required units
of measure will be requisitioned.
h. Quantity Incorporated in Unit. Indicates the quantity of the item used in the breakout shown on the illustration
figure, which is prepared for a functional group, subfunctional group, or an assembly. A "V" appearing in this column in
lieu of a quantity indicates that no specific quantity is applicable, (e.g., shims, spacers, etc).
4. Special Information.
a. Detailed assembly instructions for items source coded to be assembled are found in TM 55-4920-431-13.
Assembly components are listed immediately following the item to be assembled.
b. The following publications pertain to the APU and its components:
TM 55-4920-431-13 Test Set, Operator's, Aviation Unit and Intermediate Maintenance Manual
c. When details of an assembly are found on another text page, the description of that assembly is followed by a
notation stating where these details can be located. "Example: 161223-100, Plate Assembly, See Figure 3 for
Breakdown." The parts that make up the Plate Assembly will be found on the text listing for figure 3.
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