Proxxon 28726 Tungsten Vanadium Cutter Cylinder Round, 2-Piece One piece construction with cutting head and shaft out of a single blank Precise flutes and optimal concentricity ensure best life expectancy Tungsten vanadium steel makes bits ideal for milling, routing, profiling and slotting in materials such as hard and soft woods, non-ferrous metal, precious metal, plastics and plaster of Paris