Fully ground flute, high precision, strong self centering ability
3-flat shank giving more clamping force to the drill bits
Use with hand power drills, bench presses and pillar drills etc. Suitable for the materials such as grey cast iron, malleable cast iron, carbon steel, die-cast steel, nickel silver and graphite etc.
Special black gold treatment enhancing the surface hardness, corrosion resistance and fast chip removal