Technical burrs Optima Tools. Type: CONE. Technical specification: The unique shape of the blade with two types of teeth - coarse for fast grinding and fine for smooth grinding and finishing - allows 20% faster grinding with a quality finished surface compared to standard burrs. Carbide burrs are precise machine tools used in power and pneumatic hand tools. The working part is made of hard metal (tungsten carbide), joint with a steel shank by special technology. Application: Hardened steel, stainless steel, cast iron, nonferrous metals, fired ceramics, plastic, hard wood, especially on hard materials whose hardness can be above HRC70.