Flap Disc Abrasive Type Coated Abrasive Material Zirconia Alumina Grade Extra Coarse Backing Plate Material Fiberglass Connector Size 5/8 In.-11 Connector Type Threaded Hole Density Rating High Flap Disc Type Type 27 Overall Diameter 7 in Series BlueFire R860 Backing Material Cotton Backing Weight X Coating Coverage Semi-Open Grit P40 Maximum Operating Speed 8 600 RPM Color Blue