SAIT 55366 Closed Coat Aluminum Oxide 4-Inch x 24-Inch LA-X 100 Grit Belts - 10 Pack Manufacturer: SAIT LA-X: Economy Aluminum oxide, closed coat, X-weight cotton. For low cost sanding and finishing of ordinary and alloyed steels, ferrous and non-ferrous metals, cast iron, and wood. A good choice where price and best value is the determining factor.