Surface-Conditioning Disc Abrasive Material Aluminum Oxide Grade Very Fine Overall Diameter 6 in Series High Strength Maximum Operating Speed 4 000 RPM Connector Size 1/4 in Connector Type Unthreaded Hole Abrasive Type Non-Woven Backing Material Fiber Backing Weight X Color Maroon Grit 180-360 Resistance Properties Tear Package Quantity 70