Dremel 1/8 in. Rotary Accessory Rectangle-Shaped Tungsten Carbide for Steel,
The Dremel 9901 is a tungsten carbide cutters are ideal for shaping, smoothing or removing material from especially hard materials. Shapes, smoothaEUR(TM)s or grinds especially hard materials including: hardened steel, stainless steel, cast iron, nonferrous metals, fired ceramics, plastics and hard woods. 
 
    High speed cutter made of tungsten carbide 
    Hardest material next to diamonds 
    Shapes, smoothest, removes hard material 
    Do not run in excess of 30,000 RPM 
    Screw-free design for easy locking and loading 
    A high-speed cutter made of tungsten carbide, the hardest material next to diamonds 
    Bit diameter: 1/8 in. 
    Shank diameter 1/8 in., 3.2 mm