Flap Disc Abrasive Type Coated Abrasive Material Zirconia Alumina Grade Coarse Backing Plate Material Eco-Trim Connector Size 7/8 in Connector Type Unthreaded Hole Density Rating Standard Flap Disc Type Type 27 Overall Diameter 4 1/2 in Series ENDURO-FLEX Backing Material Fiberglass Grit 40 Maximum Operating Speed 13 300 RPM Features Trimmable