A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 6135-00-871-3646
NSN 5960-00-617-9312
NSN 5895-00-633-7623
NSN 5950-01-167-1616
NSN 6110-01-266-6752
NSN 6110-00-705-5863
NSN 5925-01-416-8176
NSN 5905-01-143-1741
NSN 6220-00-557-0436
NSN 6145-01-541-3310
NSN 5960-00-068-1457
NSN 5960-01-123-8775