Boss end hexagon in shape; has counterbore
A washer, round in shape, having a centrally located hole. One bearing surface is flat, the other surface is in the form of a raised shoulder (boss) having a flat bearing surface. Either or both of the bearing surfaces must be broken by a counterbore, countersink, or similar shaped recess. The thickness of the shoulder (boss) must not exceed 25 percent of the shoulder (boss) diameter. For items having a shoulder (boss) of greater thickness, use bearing, sleeve; bushing, sleeve; or spacer, sleeve. Excludes insulator, washer and thrust type washers.
Classification: Cotters, cotter-pins, washers and similar articles, of aluminum
NSN 6240-00-248-4281
NSN 6650-01-512-1930
NSN 5920-00-683-7883
NSN 5960-00-549-3760
NSN 6145-00-871-9112
NSN 7035-00-205-8739
NSN 5915-00-432-4580
NSN 5930-01-084-5859
NSN 5935-01-104-9942
NSN 6610-01-013-8922
NSN 5920-01-576-0181
NSN 6220-01-630-7002