This Otis Technology 12 Gauge shotgun bore brush feature phosphor bronze bristles and a brass stem that work together to offer an effective clean without damaging your barrel. Each brush is stamped with the brush size on the stem to allow for easy identification. Otis Technology 12 Gauge brushes are outfitted with 5/16-27 threads. Cleans: 12 gauge shotguns Length: 3 Inch Thread: 5/16-27 Includes: 1 Bronze Bore Brush Ideal for use with Otis Shotgun Rod with 5/16-27 threads Made in the USA