A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 5945-00-296-8464
NSN 6150-01-399-0651
NSN 6645-01-492-2808
NSN 6610-01-376-9199
NSN 6650-01-104-6139
NSN 6135-01-487-0773
NSN 6650-01-540-3606
NSN 6620-01-340-9425
NSN 5999-01-431-8878
NSN 5910-01-233-2905
NSN 6105-01-248-0195
NSN 5930-01-661-2477