The tungsten carbide indexable knives for woodworking?are made of tungsten carbide materials. They are designed with center holes so they can be installed on a spiral cutterhead. Carbide indexable insert knives are more and more popular due to their advantages of low noise and high strength which are suitable for the applications like single-sided planers, double-sided planers, four-sided planers, edge banding machines, vertical shaft machines, etc.