... drill 1)Roll forged and full polish 2)Cutting tool,metal material 3)Material:HSS ,solide carbide HSS Dril Bit, carbide ... , Mold Etc.2) Super high hardness and precision, extreme smooth coating surface, can be coated by TIN, TIALN, ALTIN, TIAIN, etc ... us. Any questions are highly welcome! tungsten carbide drill bit with coating