Tungsten Carbide Cutters are ideal for shaping, smoothing or removing material from especially hard materials. Shapes, smooths or grinds especially hard materials including: hardened steel, stainless steel, cast iron, nonferrous metals, fired ceramics, plastics and hard woods A high-speed cutter made of tungsten carbide, the hardest material next to diamonds Great for shaping those hard to work with materials Made from quality carbide steel BIT DIAMETER INCH: 1/8" BIT DIAMETER MM: 3.2 mm