Master Mechanic 7/16" x 5-1/2" High Speed Steel Black Oxide Drill Bit. It has a 135 split point, jobber length, 3/8" shank, 135 point angle with 4 cutting edges which eliminate walking and provide fast penetration. Black oxide tempering treatment reduces frictional resistance and improves chip flow. This drill bit is recommended for wood, plastic, wallboard, plywood and soft metals, aluminum, brass and bronze. It can also be used for occasional use in stainless steel and other hard metals. This drill bit is available in a bulk pack for convenience.