Silicon Polishing Wheel (Square Edge) - 800 Grit (Blue) Premium silicon-carbide wheels formulated to provide the smoothest finish without the use of messy polishing compounds. This wheel is 7/8" x 1/8" and is grit 800 (fine). Edge is square. Fine, soft and flexible. For medium lustre or smooth matte finish Operating speed range is 5000 to 10,000 rpm. Supplied as a package of a dozen.