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

This classic wool mop combines tradition with performance. It holds plenty of cleaning solution, conforms to bore grooves and includes brass components that safeguard against scratching. 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