Flap Discs Abrasive Type Coated Abrasive Material Ceramic Backing Plate Material Nylon Connector Size 5/8 In.-11 Connector Type Threaded Hole Density Rating Standard Flap Disc Type Type 27 Overall Diameter 4 1/2 in Backing Material Polyester Backing Weight Y Coating Coverage Closed Grit 60 Maximum Operating Speed 13 300 RPM Color Yellow Resistance Properties Heat