item  belongs.    This  is  necessary  since  figures  are  pre- pared   for   assembly   groups   and   subassembly   groups, and listings are divided into the same groups. (2) Second.        Find    the    figure    covering    the assembly group or subassembly group to which the item belongs. (3) Third.    Identify  the  item  on  the  figure  and use the Figure and Item Number Index to find the NSN. b. When National Stock Number or Part Number Is Known: (1) First.  Using the National Stock  Number  or Part   Number   Index,   find   the   pertinent   National   Stock Number or Part Number.  The NSN Index is in National Item  Identification  Number  (NIIN)  sequence  (see  para- graph  4.a.(1)).    The  part  numbers  in  the  Part  Number index are listed in ascending alphanumeric sequence (see paragraph 4.b).    Both  Indexes  cross-reference  you to the Illustration/figure and Item number of the item you are looking for. (2) Second.        Turn    to    the    figure    and    item number, verify that the Item Is the one you’re looking for, then locate the item number in the repair parts list for the figure. 7.     Abbreviations. For  standard  abbreviations  see  MIL-STD-12D,   Military Standard Abbreviations for Use on Drawings, Specifications, Standards, and in Technical Documents. Abbreviations Explanation NIIN  .................... National item Identification Number (consists of the last 9 digits of the NSN) RPSTL................. Repair Parts and Special Tools List 5