Specification:caliber from 3mm to 8mm, total height 70mm , head of drill height 25mm. characterist Specification:caliber from 3mm to 8mm, total height 70mm , head of drill height 25mm. characteristic: 1.same hardness HV550, edge is very sharp and lasting. used in each kind paper drilling 2.according your required custom-made different kinds size

Drill bits