Aluminum Oxide Connector Size 3/8 in Connector Type Unthreaded Hole Grit 24 Overall Diameter 4 in Overall Thickness 1/2 in Compatible Tool Type Bench Grinder Centerless Grinder Cylindrical Grinder Pedestal Grinder Tool and Cutter Grinder Primary Material Applicationn Aluminum Brass Bronze Cast Iron Copper Steel Specification 57A24-P5BRA Wheel Hardness P Wheel Type Type 1 Maximum Operating Speed 11 940 RPM Series 57A Grade Extra Coarse Bond Type Resin Color Black