Our black oxide jobber length drill bits are a general purpose drill bit made from high-speed steel and coated with a black oxide coating for lubricity and resistance to corrosion. These drill bits feature a 135* split point which prevents the drill bit from "walking" and eliminates the need for a pilot drill and are ideal for medium to light tensile strength metal drilling. This set goes from 1/16"-1/2" by 64ths and contains 29 pieces. Made in the USA by Norseman Drill & Tool.