Cut-Off & Grinding Wheel, Abrasive Material Aluminum Oxide, Connector Size 7/8 in, Connector Type Unthreaded Hole, Grit 24, Overall Diameter 4 1/2 in, Overall Thickness 0.125 in, Primary Material Application Cast Iron, Masonry, Steel, Compatible Tool Type Angle Grinder, Series Metal AO, Wheel Type Type 27, Maximum Operating Speed 15,200 RPM, Grade Extra Coarse