Master Mechanic 15/32" x 5-3/4" High Speed Steel Black Oxide Drill Bit for drilling through a variety of materials, including wood, plastic, wallboard, plywood, soft metals, aluminum, brass, and bronze. It features a 135 split point, jobber length, 3/8" shank, and 135 point angle with 4 cutting edges that eliminate walking and provide fast penetration. The black oxide tempering treatment reduces frictional resistance and improves chip flow. This drill bit is recommended for occasional use in stainless steel and other hard metals. It comes in a bulk pack for convenience.