TM 10-3930-665-13&P 3.  EXPLANATION OF COLUMNS (SECTIONS II AND III) (CONT) Source Maintenance Recoverability Code Code Code XX 1st two XX X positions How you get an item. 3d Position 4th position Who determines disposition action Who can install Who can do on an unserviceable replace or use complete repair* item. the item. on the item. *Complete  Repair:    Maintenance  capacity,  capability,  and  authority  to  perform  all  corrective  maintenance  tasks  of  the "Repair" function in a use/user environment in order to restore serviceability to a failed item. (1) Source Code.  The source code tells you how to get an item needed for maintenance, repair, or overhaul of an end item/equipment.  Explanations of source codes follow. Code Explanation PA PB PC** PD PE PF PG KB KD KF Stocked items; use the applicable NSN to request/requisition items with these source codes.  They are authorized to the level indicated by the code entered in the 3d position of the SMR code. **NOTE:  Items coded PC are subject to deterioration. Items  with  these  codes  are  not  to  be  requested/requisitioned  individually.    They  are  part  of  a  kit which  is  authorized  to  the  maintenance  level  indicated  in  the  3d  position  of  the  SMR  code.    The complete kit must be requisitioned and applied. 2