A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 5895-01-620-1392
NSN 6220-01-388-9701
NSN 6610-01-445-7679
NSN 6620-01-162-8001
NSN 5985-00-543-1861
NSN 2925-01-457-5649
NSN 6685-01-524-4348
NSN 5920-01-353-6423
NSN 5990-01-538-6115
NSN 5835-00-833-7080
NSN 6320-00-809-5744
NSN 5960-01-412-9474