Silicon Polishing Cone - 800 Grit (Blue) Premium silicon-carbide wheels formulated to provide the smoothest finish without the use of messy polishing compounds. Cone is mounted on 3/32" shank. This cone is 5/8" x 7/32" and is grit 800 (fine). 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.