A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 5965-01-207-0991
NSN 6150-00-132-8997
NSN 6110-01-327-9256
NSN 6650-01-387-1740
NSN 5835-01-024-9249
NSN 6150-01-437-5552
NSN 5895-00-894-4860
NSN 5935-01-141-7694
NSN 6650-00-983-6722
NSN 5996-00-153-3216
NSN 5960-01-048-0975
NSN 6220-01-330-8238