A cylindrically-shaped headed item, having circular or longitudinal groove(s).
NSN 5950-00-455-6818
NSN 6135-00-444-1402
NSN 6620-00-937-5931
NSN 5905-00-010-6393
NSN 6320-00-433-2773
NSN 6650-01-553-2805
NSN 4140-00-555-3856
NSN 5960-01-589-6846
NSN 5855-00-631-4565
NSN 6220-01-090-0126
NSN 5996-00-902-3445
NSN 6145-00-141-8095