Depressed Center Grinding Wheel Abrasive Material Ceramic Connector Size 7/8 in Connector Type Unthreaded Hole Grit 24 Overall Diameter 4 1/2 in Overall Thickness 0.25 in Primary Material Applicationn Nickel Alloy Stainless Steel Steel Compatible Tool Type Angle Grinder Series SG24N Wheel Type Type 27 Maximum Operating Speed 13 300 RPM