A cylindrically-shaped headed item, having circular or longitudinal groove(s).
NSN 4140-00-806-7201
NSN 6150-00-882-7247
NSN 2925-01-415-2140
NSN 6320-00-831-2227
NSN 5996-01-190-5160
NSN 5930-01-184-5183
NSN 5920-01-502-9681
NSN 7035-01-604-9807
NSN 6320-01-039-5891
NSN 5998-01-572-5289
NSN 5950-01-507-0909
NSN 5985-00-722-7462