A cylindrically-shaped headed item, having circular or longitudinal groove(s).
NSN 6220-00-354-8287
NSN 6150-00-854-1887
NSN 7035-01-650-4589
NSN 4140-01-634-0330
NSN 5975-01-381-6933
NSN 6320-01-138-0442
NSN 5925-01-252-0199
NSN 5985-00-727-8776
NSN 6220-01-490-1551
NSN 5915-01-515-0156
NSN 5998-01-202-1963
NSN 7035-00-488-9765