TM   10-3930-660-24P (8) In the Special Tools List section,   the basis of issue (BOI) appears as the last line(s) in the entry for each special tool and other special support equipment. When density of equipments supported exceeds density spread indicated in the basis of issue, the total authorization is increased proportionately. f. QTY (Column (6)). The QTY (quantity per figure column) 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 the quantity is variable and the quantity may vary from application to application. 4. Explanation of Columns (Section IV). a.  NATIONAL  STOCK  NUMBER  (NSN)  INDEX. (1) STOCK NUNBER Column. This column lists the NSN by National item identification number (NIIN) sequence. The NIIN consists of the last nine digits of the  NSN,  for  example: NSN NIIN When using this column to locate an item,   ignore the first 4 digits of the NSN. However, the complete NSN should be used when ordering items by stock number. (2)  FIG.  Column. This column lists the number of the figure where the item is identified/located. The figures are in numerical order in Section II and Section III. (3)  ITEM  Column. The item number identifies the item associated with the figure listed in the adjacent FIG. column. This item is also identified by the NSN listed on the same line. b. PART NUMBER INDEX. Part numbers in this index are listed by,part ascending alphanumeric sequence (i.e.,   vertical arraangement of letter and combination which places the first letter or digit of each group in order Z, followed by the numbers O through 9 and each following letter or digit order) . number in number A through in like (1)  CAGE  Column. The Federal Supply Code for Manufacturer (CAGE) is a 5-digit numeric code used to identify the manufacturer, distributor or Government agency, etc., that supplies the item. (2) PART NUMBER Column. Indicates the primary number used by the manufacturer (individual, firm, corporation or Government activity), which controls the design and specifications of the item by means of its engineering drawings, specifications standards and inspection requirements to identify an item or range of items. (3) number and STOCK  NUMBER  Column  . This column lists the NSN for the associated manufacturer identified in the PART NUMBER and CAGE columns to the 6 part left.