The flutes of the new RUKO high-performance taper and deburring countersinkers are CBN ground from the fully hardened material. Because CBN (cubic crystalline boron nitride) is a much harder abrasive than even silicium carbide or corundum, a better and sharper cutting edge is achieved - without burrs. And, with higher dimensional precision the countersinkers will last considerably longer while maintaining the precise tolerances.
