5pc set of diamond-vented cutting discs with a 22 mm diameter and a 3,2 mm replaceable mandrel. Ideal for cutting or sharpening of materials harder that metal, such as marble, stone, porcelain, ceramic, and hardened resin. Guarantees extreme precision when cutting and long durability. The discs are only intended to cut along their edge. Please be safe and do not expose the discs to lateral pressure, do not try to use them for sanding or for carving. Max.speed 28.000rpm.