Quality: The Elitexion Aluminum Oxide Resin Discs was designed to help you on the job to strip, grind, remove welding excess, deburr, remove rust, and remove paint. The discs needs to be used with the angle grinder and packing pad with nut. Also it can help you polish ferrous and non-ferrous metals, wood and fiberglass. The discs are made of aluminum oxide grain. Multipurpose: -Remove welding excess -Remove rust -Remove paint -Strip, grind and deburr Package Includes: Pack of 20 pcs Discs 8pcs of 100 Grit, 4pcs of 60 Grit, 4pcs of 50 Grit, and 4pcs of 40 Grit. Dimension: Diameter of disc is 4-1/2” and the harbor hole is 7/8”.