Flap Disc, Abrasive Type Coated, Abrasive Material Ceramic, Grade Medium, Backing Plate Material Fiberglass, Connector Size 7/8 in, Connector Type Unthreaded Hole, Density Rating Standard, Flap Disc Type Type 27, Overall Diameter 4 1/2 in, Series 769F, Backing Material Polyester, Backing Weight YF, Coating Coverage Open, Grit 60, Maximum Operating Speed 13,300 RPM