Flap Disc, Abrasive Type Coated, Abrasive Material Zirconia Alumina, Grade Medium, Backing Plate Material Phenolic, Connector Size 5/8 In.-11, Connector Type Threaded Hole, Density Rating Standard, Flap Disc Type Type 27, Overall Diameter 4 1/2 in, Quick Change System Not Applicable, Series Tiger X, Backing Material Cloth, Backing Weight X, Grit 60, Maximum Operating Speed 13,000 RPM