Outfit your floor buffer with this Screen-Bak Durite Q421 SC fine grit screen floor sanding disc for excellent cutting with extreme resistance to loading. A P-graded sharp silicon carbide grit and an open-weave screen provide durable sanding ideal for removing scale, rust and corrosion from concrete and hardwoods. The durable waterproof disc is more durable than paper or cloth and can be rinsed and reused to extend its useful work life.