H7339 Flap Disc Abrasive Type Coated Abrasive Material Zirconia Alumina Grade Extra Coarse Backing Plate Material Aluminum Connector Size 7/8 in Connector Type Unthreaded Hole Density Rating Standard Flap Disc Type Type 29 Overall Diameter 4 1/2 in Quick Change System Not Applicable Series Tiger Aluminum Back Backing Material Aluminum Grit 36 Maximum Operating Speed 13 000 RPM