Pro-Shot's Chamber Maid Chamber Stars remove carbon and fouling build-up in the locking lug recesses of your favorite AR rifle fast & easy! Just thread onto bore brush and rotate inside lug recesses to remove gunk that was broken loose by using a chamber brush. Chamber star US Patent# 0562,935 Chamber Star Swab Features: Applies CLP or oil evenly in Star Chamber Removes loosened fouling/carbon from 5.56mm/.223 Cal. Star Chamber Threads onto Standard 5.56mm/.223 Cal. bore brush (Nylon Bristle Recommended) Strong and Absorbent Industrial Wool Felt Full AR Lug Recess Pattern - Patented Design (Chamber Star US Patent# 0562,935) Made in USA