The Pro-Shot 12 Gauge Oversized Chamber Brush is a purpose-built cleaning tool for maintaining shotgun chambers and removing stubborn deposits that can remain after routine bore cleaning. Its 20mm brush diameter is sized for the chambers of most 12 gauge shotguns, giving the bristles the contact needed to scrub areas where powder residue, carbon and plastic wad fouling can accumulate. This makes it a practical addition to the cleaning bench for hunters, clay-target shooters and other shotgun owners who want a dedicated tool for chamber maintenance rather than relying on a standard bore brush. Heavy-duty bronze bristles provide firm cleaning action, while the thick twisted core terminates in a loop instead of an exposed sharp point. That construction adds strength and helps reduce the chance of an unfinished wire end contacting the firearm. The brush uses a direct #5/16-27 thread, the standard American shotgun accessory thread, so it can attach to a compatible shotgun cleaning rod without a separate brush coupling. It may also be paired with a suitable drill rod or compatible drill adapter when powered chamber cleaning is appropriate. The direct-thread design is especially useful for addressing heavy fouling in shotgun chambers and choke areas, although users should always follow the firearm and cleaning-tool manufacturers' instructions when selecting a rod, adapter or powered method. This model is supplied in a reusable tube that protects the bristles during storage and helps keep fouling away from other cleaning equipment. Made in the USA, this is the oversized 12 gauge configuration with bronze bristles, a 20mm diameter and #5/16-27 threading; it is the brush only and does not include a handle, cleaning rod, drill or adapter.Specifications and Features: 20mm oversized brush for 12 gauge shotgun chambers Heavy-duty bronze bristles for stubborn fouling Looped core end for strength and surface protection Direct #5/16-27 American shotgun thread Attaches to compatible shotgun cleaning or drill rods Reusable storage tube Made in the USA Weight: 4 oz Brand: Pro-Shot Model: 12SB Product Type: Shotgun Chamber Brush Manufacturer Part Number: 12SB UPC: 709779101009