Grit is a term used to describe the coarseness of abrasive sand bits. It is measured on a scale from 0 to 100, with 0 being the finest and 100 being the coarsest. Abrasive sand bits are used for grinding, polishing, and sanding materials such as metal, wood, and stone. They are available in a variety of sizes and shapes, and the GRIT size determines the size of the particles that make up the bit.