Fiber Disc Abrasive Type Coated Abrasive Material Aluminum Oxide Backing Material Fiber Backing Weight YY Grit 36 Overall Diameter 4 1/2 in Series Aluminum Oxide Coating Coverage Closed Maximum Operating Speed 11 000 RPM Connector Size 7/8 in Connector Type Unthreaded Hole Color Red Grade Extra Coarse Package Quantity 25