The X-LOCK Type 27 General Purpose Abrasive Grinding Wheels are ideal for the general grinding of ferrous metals, including alloy steel, carbon steel, stainless steel, cast iron, and wrought iron. These wheels are constructed of high-purity white aluminum oxide abrasive grains for increased performance and added durability. The X-LOCK quick change system provides up to 5x faster wheel changes vs. a standard angle grinder mount. Simply pull the release lever on the X-LOCK Angle Grinder and change the wire cup brush no tools are needed. These wheels are designed to be used with Makita X-LOCK Angle Grinders (XAG25, XAG26, and GA4570 sold separately) or any angle grinder with a 7/8 In. arbor.