Flap Wheel, Abrasive Material Aluminum Oxide, Abrasive Type Coated, Backing Material Cotton, Backing Weight X, Grit P180, Series Super Finish, Flap Width 1/2 in, Maximum Operating Speed 20, 000 RPM, Shank Size 1/4 In. -20, Overall Diameter 3 in, Grade Fine, Shank Type Threaded, Coating Coverage Closed