Extra long length dream drill bits with coolant holes. Right hand spiral, 30 degree helix. 140 Degree point angle. Made of Carbide. Shank tolerance ød2: -0.0/-0.0005. 8xD. Application for drilling into steel in general, cast steel, cast iron, chilled cast iron, malleable cast iron, non-ferrous heavy metal, non-ferrous light metal, abrasive plastic. Advantage: Self centering (center drilling is not required); Excellent positioning (bush is not necessary) and Special Design (reaming is not required, good chip removal, powerful drilling).