SE GC121B 38-Piece Gun Cleaning Brush Kit (12) Brass Brushes; (12) Nylon Brushes; (12) Stainless Steel Brushes; (1) Ball-Bearing, Quick-Release Rubberized Handle Driver; (1) 6" Extension Shaft Cleans Bore Sizes (cal.): .32, .325, .38, .380, .357, .35, .38, .40, .44, .475, .480, .50, .57, .68 Plastic Index Case w/ the Brush Sizes Stamped Inside Compatible with Most Standard Drills Dozens of Uses and Applications for this Brush Set Beyond Conventional Gun Cleaning