A cylindrically-shaped headed item, having circular or longitudinal groove(s).
NSN 5998-01-473-9216
NSN 5990-01-027-8260
NSN 6240-00-194-7924
NSN 6220-01-078-8576
NSN 6135-01-393-4746
NSN 5999-01-429-0149
NSN 5960-01-553-4557
NSN 6220-01-626-0513
NSN 5990-01-180-7365
NSN 5930-01-135-0693
NSN 5910-01-519-8236
NSN 5975-00-950-6411