A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 6650-01-105-9500
NSN 5960-00-636-4834
NSN 6650-01-392-8020
NSN 5920-00-584-4592
NSN 5915-01-494-3176
NSN 6240-01-607-6252
NSN 5915-00-583-4229
NSN 5996-01-488-4976
NSN 5960-01-252-8821
NSN 5950-01-631-2024
NSN 5990-01-473-4314
NSN 5945-01-315-3818