Flaring Cup Grinding Wheel Abrasive Material Aluminum Oxide Back Thickness 3/4 in Connector Size 5/8 In.-11 Connector Type Threaded Hole Grit 16 Overall Diameter 4 in Overall Thickness 2 in Rim Thickness 3/4 in Primary Material Applicationn Aluminum Brass Bronze Cast Iron Copper Steel Nickel Alloy Stainless Steel Titanium Tool Steel Compatible Tool Type Cup Grinder Specification 57A16-Q Wheel Hardness Q Wheel Type Type 11 Maximum Operating Speed 9 070 RPM