SQUARE. Built for maximum durability and long life with impact drivers. Forged bit for superior fit, which reduces stripping and increases life of bit 3X. Manufactured with heavy-duty, cold-forged, high-grade steel to withstand high torque output. Black oxide finish resists corrosion and increases life of bit. Shank diameter 1/4”. Overall length 2”. Point size #2 SQ. Overall length 6”.