Aluminum Oxide Connector Size 12 in Connector Type Unthreaded Hole Grit 60 Overall Diameter 20 in Overall Thickness 8 in Compatible Tool Type Centerless Grinder Primary Material Applicationn Cast Iron Steel Tool Steel Specification 64A60-KVCE Wheel Hardness K Wheel Type Type 1 Maximum Operating Speed 1 625 RPM Series 64A Grade Medium Bond Type Vitrified Color Gray Item Straight Grinding Wheel