TM 10-3610-202-14 d.      Column   4,   Maintenance   Level.      Column   4 specifies,   by   the   listing   of   a   work   time   figure   in   the appropriate subcolumn(s), the lowest level of maintenance authorized to perform the function listed in column    3.        This    figure    represents    the    active    time required   to   perform   the   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  will  be  shown  for  each level.  The number of man-hours specified by 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,   troubleshooting   time,   and quality  assurance/quality  control  time  in  addition  to  the time required to perform the specific tasks identified for the maintenance functions authorized in the maintenance allocation chart.  The symbol designations for the various maintenance levels are as follows: C Operator or crew O Organization maintenance F Direct support maintenance H General support maintenance D D Depot maintenance e.   Column  5,  Tools  and  Equipment .    Column  5 specifies,    by    code,    those    common    tool    sets    (not individual   tools)   and   special   tools,   test,   and   support equipment required to perform the designated function. f. Column 6, Remarks.  This column shall contain a letter code in alphabetic order which shall be keyed to the remarks contained in Section IV. C-4.    Column    Entries    Used    in    Tool    and    Test Equipment Requirements. a. Column 1, Tool or Test Equipment Reference    Code.        The    tool    and    test    equipment reference  code  correlates  with  a  maintenance  function on the identified end item or component. b. Column   2,   Maintenance   Level.      The   lowest level of maintenance, authorized to use the tool or test equipment. c. Column 3, Nomenclature. Name or identification of the tool or test equipment. d. Column    4,    National/NATO    Stock    Number. The National or NATO stock number of the tool or test equipment. e. Column 5, Tool Number.    The  manufacturer's part number. C-5.    Explanation of Columns in Section IV. a. Reference  Code.    The  code  scheme  recorded in column 6, Section II. b. Remarks. This column lists information pertinent  to  the  maintenance  function  being  performed as indicated on the MAC, Section II. C-2