Carbide Rotary Burrs, often mentioned as rotary files or die grinder bits, are used to cut, shape, grind, and remove sharp edges, burrs, and excess material (deburring). A rotary burr is a rotating tool that's used for removing material. They're designed to rotate at high speed, enabling it to control the fabric it's performing on. Burrs are suitable for deburring, shaping, and enlarging holes when working with metal.