Recessed Grinding Wheel, Abrasive Material Aluminum Oxide, Connector Size 1 1/4 in, Connector Type Unthreaded Hole, Grit 46, Overall Diameter 8 in, Overall Thickness 1 in, Wheel Hardness J, Specification 32A46-JVBE, Wheel Type Type 5, Compatible Tool Type Cylindrical Grinder, Surface Grinder, Primary Material Applicationn Aluminum, Cast Iron, Stainless Steel, Steel, Tool Steel, Maximum Operating Speed 3,600 RPM, Recess Depth 1/2 in, Recess Diameter 3 1/4 in, Bond Type Vitrified, Color Gray