Fiber Disc, Abrasive Type Coated, Abrasive Material Zirconia Alumina, Backing Material Fiber, Backing Weight Not Rated, Grit 50, Overall Diameter 4 1/2 in, Series V1247, Maximum Operating Speed 11,000 RPM, Resistance Properties Tear, Connector Size 7/8 in, Connector Type Unthreaded Hole, Color Blue, Grade Coarse, Package Quantity 25