Forney 71769 7-Inch Aluminum Oxide Sanding Disc with 7/8-Inch Arbor, 80-Grit Excellent quality aluminum oxide steel sanding and grinding disc Ideal for weld grinding, blending, finishing, deburring and other general purpose applications Can be used on most types steel as well as fiberglass and plastics Uses a special heat treated ceramic coated aluminum oxide grain for cutting action and long life