Diamond Wheel Inc. makes CBN (Cubic Boron Nitride or Borazon) grinding wheels for professional chainsaw chain sharpening. CBN replacement wheels are designed to sharpen standard (non-carbide) chainsaw chains. They are pre-shaped and unlike aluminum oxide wheels will hold their shape. Diamond Wheel Inc. CBN wheels have an aluminum core to run cooler, create very little dust, and are known to sharpen 100's of chains before a replacement is needed. CBN wheels are not designed for carbide chainsaw chains. Carbide chains will destroy these wheels.