Brownells 20 Gauge 5/16-27 Male Bore Mop, Pack of 12

Clean thoroughly with this highly absorbent virgin wool mop. Its springy texture reaches into rifling for even coverage and the twisted brass shank won't harm your barrel's interior. Material composition includes wool fibers, brass shank and precision-engineered coupling components for enhanced durability and performance 2.87 inches length, 5/16-27 thread