This Flexible Grinding Wheel contains 3M Ceramic Abrasive Grain, which offers exceptional durability and improved cutting efficiencies. The unique "stay sharp" crystalline structure of the ceramic grain continually generates fresh cutting edges on the surface of the workpiece, ensuring an exceptionally fast and sustained cut. The fast and uniform cutting action helps to increase productivity and throughput. Additionally, the grain can withstand medium to high pressure production environments, contributing to the abrasive's long service life. These wheels should not be used on tools without guards.