Flap Disc, Abrasive Type Coated, Abrasive Material Zirconia Alumina, Grade Coarse, Backing Plate Material Fiberglass, Connector Size 5/8 In.-11, Connector Type Threaded Hole, Density Rating Standard, Flap Disc Type Type 29, Overall Diameter 4 1/2 in, Series XC1176, Backing Material Fiberglass, Backing Weight Y, Grit 80, Maximum Operating Speed 13,300 RPM