application  and  appears  in  an  APL,  stock  number sequence list (SNSL), integrated stock list (ML), Naval Ship  Systems  Command  drawings,  or  a  manufacturer’s handbook.  Section  A  of  Part  III  of  the  COSAL  (SNSL of  storeroom  items)  lists  equipment-related  consumable and  repair  parts  normally  stocked  by  the  supply department.  Any  item  in  Section  A  is  considered  a repair  part. CONSUMABLE—administrative and housekeeping  items,  common  tools,  paints,  cognizance symbol 11 forms, or any other items not specifically defined as equipage or repair parts. Materials such as general-purpose   hardware,   metals,   lumber,   and lubricating oil also are considered to be consumable in procurement  transactions.  But,  they  are  be  treated  as repair  parts  in  shipboard  issue  transactions  when  the material  is  to  be  used  to  accomplish  maintenance actions. REPAIRABLE— a component or part designated by the cognizant inventory manager as an item which can   be   economically   repaired   when   it   becomes unserviceable,   Repairable   items   are   identified   by material control code (MCC) D, E, G, H, Q, or X. MCC D items maybe disposed of locally when they become unserviceable   and   cannot   be   repaired   (by   an organizational  or  intermediate  maintenance  activity. MCC E, G, H, Q, and X items are mandatory turn-in repairable. These  items  must  be  transferred  to  a designated depot level repair facility collection point (see  indicated  in  the  Master  Repairable  Item  List (MRIL))  when  they  become  unserviceable  and  cannot be  locally  repaired.  (See  NAVSUP  P-485,  for  more information.) CIRCUIT   SYMBOL—   used   for   electronic equipment in the same way that part numbers, drawing numbers,  etc.,  are  used  for  other  equipment.  Most circuit  symbol  numbers  are  cross-referenced  in  the APLs  to  an  NSN  for  the  particular  part  required. END   ITEM—   a   combination   of   products, component parts, and/or materials that are ready for final intended use. It is an equipment of one of its major subdivisions. ARTICLE-a  collection  of  items  within  a  class (e.g., ensign, all nations or hats, white all sires). ITEM— each size or color, of an article (e.g., ensign U.S.  No.  7). REPLACEMENT ITEM—  an item supplied as a spare  or  repair  part  in  place  of  the  original  part. Replacement  items  are  not  necessary  interchangeable with the items they replace. They may be of better quality or may have greater capacity. Replacement items are not substitutes because they are supplied on a continuing basis. MAKE ITEM— an item that is made from raw or bulk  stock  or  by  modifying  other  stocked  items.  They are not procured for stock or issue in finished form. Make  items  are  source  coded  “MF”  or  “MO”  in  the COSAL. EQUIVALENT ITEM— an item similar to another item  to  the  extent  that  its  characteristics  are  in  strict accordance  with  the  specifications  for  the  item  it  may replace. Repairable assemblies are equivalent only if their “purchased repair parts” and performance are also equivalent. “Purchased repair parts” are limited to those  items  of  a  design  peculiar  to  the  repairable assembly  concerned. INTERCHANGEABLE ITEM— a  nonequivalent item  used  in  place  of  another  item  in  all  application SUBSTITUTE ITEM—  an item authorized for one-time  use  in  place  of  another  item,  based  on  a specific   application   and   request.   Equivalent   or interchangeable items are not included in the term “substitute items.” No substitute will be used that might adversely  affect  any  of  the  following: 1. 2. 3. 4. Safety   of   flight   (considering   all   primary structure  and  equipment); Efficient performance of any aircraft, engine, accessory,  or  equipment; Manufacturer’s  guarantee  or  warranty;  or Delicate,  sensitive,  or  critical  assemblies,  or those  subject  to  environmental  condition,  high speed, or high loads. The  authority  for  a  substitute  is  automatically  canceled as soon as a substitution is made. Additional requests for  the  same  substitute  item  must  be  considered separately and entirely on the merits which justify its preference. ACCESSORY— a part, subassembly, or assembly designed  for  use  in  conjunction  with  or  to  supplement another assembly, unit, or set. It contributes to the effectiveness  of  the  accessory  without  extending  or varying the basic function of the assembly or set. An accessory   may   be   used   for   testing,   adjusting,   or calibrating purpose (e.g., test instrument, recording camera for radar set, headphones, emergency power Supply). 4-5