Made of high-quality aluminum oxide, which greatly improves the speed, power, service life, and durability. Unique design to promote heat dissipation, avoiding metal thermal burns, and reducing material loss during cutting. Designed to be used on an air cutting tool, small angle grinder, die grinder, or die cutter. Used on cast iron, steel, stainless steel, aluminum, fiberglass, and plastic, as well as several other alloys. 7/8" Metal Reinforced Arbor Hole. Type: 41 MAX RPM: 15,200