This Bosch bonded abrasive wheel is made with high-quality Aluminum Oxide grain for exceptional speed and durability in tough environments for hard-to-reach grinding or blending applications. The grain's high-tensile strength helps prevent fracturing. Specially formulated resinoid bonds are applied to help ensure long wheel life. Multiple layers of long, stranded fiberglass are woven to form an exceptionally strong reinforcement layer to stand up to tough metal-grinding jobs. This Type 27 wheel features a depressed center wheel designed for grinding. It is an optimal match with the Bosch GWS12V-30 3 In. grinder. It is compatible with standard 3 In. grinders and cut saws with 3/8 In. arbors.