The only substance harder than tungsten carbide is diamond. Dremel tungsten carbide Cutters are ideal for shaping, smoothing or removing material from especially hard substances, like cast iron, nonferrous metals, and hard woods. The 1/8-inch tungsten carbide cutter can be used in virtually any Dremel rotary tool.
Dremel - 1/8 In. Tungsten Carbide Cutter
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