Our Black & Gold finish letter size drill bits are made from high-molybdenum steel for high strength and long life. They feature a 135* split-point for quickly sinking into hard metals without the drill bit "walking". They are excellent for drilling hardened steels and stainless steels. The black & gold finish provides lubricity for easier cutting and they are heat treated by nitro-carburizing for added strength. Made in the USA by Norseman Drill & Tool.