Features These center drill bits are used in metalworking to provide a starting hole for a larger-sized drill bit. Center Drill Bit Made from high speed steel, these center drill bits are of high hardness and good wear resistance,high strength, high cost performance. They can also be used to make a conical indentation in the end of a workpiece in which to mount a lathe center. There are total 5 pieces center bits in this set that can be used to drill holes in different sizes,More professional and practical. Center Drill Bit Widely used on lathe machines, these center drill bits can cutting easily and remove chips smoothly. Specifications: Material: High speed steel Angle: 60° Cutting Edge Diameter 1.5mm 2mm 2.5mm m 4mm Shank Diameter 5mm 5mm 6mm 8mm 10mm Length 35mm 41mm 45mm 51mm 60mm Quantity: 5pcs Package Includes: 5 x Center Drill Bits Package List