H7304 Flap Disc Abrasive Type Coated Abrasive Material Zirconia Alumina Grade Extra Coarse Backing Plate Material Fiberglass Connector Size 5/8 in Connector Type Unthreaded Hole Density Rating Standard Flap Disc Type Type 29 Overall Diameter 4 in Series BlueFire R884P Backing Material Cotton Backing Weight Y Coating Coverage Semi-Open Grit P40 Maximum Operating Speed 15 300 RPM Color Blue