Untized discs, obtained from pressed layers of non-woven fabric, guarantee an excellent surface finish,cold grinding, reduced clogging and long life. The 3SF version in Silicon Carbide is more flexible and suitable for small burrs, cleaning of welding traces and polishing. The more rigid and agrresive 6AM version in Aluminum Oxide is suitable for burrs and bevels even on edges. 22.23 mm hole for use on angle grinders. Max speed 10,000 RPM - Recommended 5,000RPM