A cylindrically-shaped headed item, having circular or longitudinal groove(s).
NSN 6240-01-137-5888
NSN 5996-00-034-5077
NSN 6145-01-421-1533
NSN 5910-00-618-5455
NSN 5950-01-230-6575
NSN 7035-01-584-1350
NSN 5965-01-036-1325
NSN 5925-01-150-6502
NSN 5835-00-180-7555
NSN 6150-00-230-6919
NSN 4140-00-679-9512
NSN 5835-01-317-4840