Aluminum Oxide, Connector Size 5 in, Connector Type Unthreaded Hole, Grit 60, Overall Diameter 12 in, Overall Thickness 1 1/2 in, Compatible Tool Type Cylindrical Grinder, Surface Grinder, Tool and Cutter Grinder, Primary Material Applicationn Aluminum, Cast Iron, Stainless Steel, Steel, Tool Steel, Specification 32A60-KVBE, Wheel Hardness K, Wheel Type Type 1, Maximum Operating Speed 2,070 RPM, Series 32A, Grade Medium, Bond Type Vitrified, Color Purple, Item Straight Grinding Wheel