Innovative Products Of America 8081 6 Piece Brass Bore Brush Set, 8, 10, 12, 15, 17, and 19 mm Twisted-wire bore brush set featuring the most common sizes Durable and abrasive bore brushes 6-piece set (8, 10, 12, 15, 17, and 19mm sizes) 1/4" hex shank Available in stainless steel (#8080) and brass (#8081) - do not exceed 600 rpm