Depressed Center Cut-Off Wheel, Abrasive Material Aluminum Oxide, Connector Size 7/8 in, Connector Type Unthreaded Hole, Grit 60, Overall Diameter 6 in, Overall Thickness 0.045 in, Primary Material Application Steel, Compatible Tool Type Angle Grinder, Series A60S, Wheel Type Type 27, Maximum Operating Speed 10,200 RPM, Grade Medium The SAIT(TM) Type 27 general-purpose grinding and cutting wheel has an aluminum oxide abrasive for cutting ferrous metals.