Otis' Bore Brushes have a proprietary Tufcor core wire that is corrosive-resistant and has a tighter twist for better bristle retention with twice the fill of other brushes with bristles right to the end. Each brush features the size stamped on the stem and color-coded core wire to easily identify the brush size. Includes: .22/.27/.30/.38/.45 caliber bronze brushes. Size .22-.45 Cal Type Bore Brush Series Brush Includes .22/.27/.30/.38/.45 Caliber Bronze Brushes Material Brass Quantity 10 Pack Bristle Type Bronze Suitable For Firearms