Depressed Center Grinding Wheel Abrasive Material Aluminum Oxide Connector Size 7/8 in Connector Type Unthreaded Hole Grit 24 Overall Diameter 5 in Overall Thickness 0.25 in Primary Material Applicationn Cast Iron Stainless Steel Steel Compatible Tool Type Angle Grinder Series Gemini Wheel Type Type 27 Maximum Operating Speed 12 225 RPM Grade Extra Coarse