TM 5-4220-231-14&P APPENDIX  D EXPENDABLE/DURABLE SUPPLIES AND   MATERIALS LIST Section I.    INTRODUCTION D-1. SCOPE. This    appendix lists   expendable supplies and    materials you   will  need    to   operate and    maintain the    Special Diver   Air Support System (SDASS). This    listing    is  for   informational purposes only,   and    is  not  authority to   requisition the    listed items. These items are    authorized to   you    by   CTA    50-970, Expendable/Durable Items    (except Medical, Class V, Repair Parts, and    Heraldic Items),    or   CTA    8-100,     Army    Medical     Department Expendable/Durable Items. D-2. EXPLANATION OF   COLUMNS a. Column (1). Item   Number. This    number is   assigned to  the    entry    in  the    listing   and     is   referenced in  the    narrative instructions to   identify    the    material (e.g.,    "Use    cleaning solution, item    16,   App.    D"). b. Column (2). Level. This    column     identifies the   lowest     level    of  maintenance that    requires the   listed item. C - Operator/Crew O - Organizational Maintenance F - Direct    Support Maintenance H - General Support Maintenance C. Column     (3).    National     Stock    Number. This    is  the    National    Stock     Number    assigned to  the   item;   use it  to   request or   requisition the    item. d. Column     (4).    Description. Indicates     the    Federal    item   name    and,    if required, a  description to  identify the   item. G. Column (5). Unit   of    Measure (U/M). Indicates the     measure used in   performing the    actual maintenance function. This     measure is  expressed by  a   two-character alphabetical abbreviation (e.g.,     ea,     in,  pr). If the unit   of    measure differs     from    the    unit   of    issue, requisition the    lowest unit    of   issue that     will   satisfy     your requirements. D-1