Stone cutting disc, or cut-off wheel, is a thin, rigid abrasive disc used with power tools like angle grinders to precisely cut hard materials such as stone, concrete, tile, and brick. They are made from an abrasive material like silicon carbide or diamond grit, bonded together with resin and reinforced with fiberglass for strength and safety. The disc rotates at high speed to remove material through an abrasive or erosion process, and it is crucial to use the correct disc for the specific material and to never exceed the disc's maximum RPM to prevent breakage and injury.