Irwin 1837403 Torx T20 x 1" Impact Insert Bits - 25 per Bag T20 Torx Point x 1" Overall Length with 1/4" Hex Shank Built for maximum durability and long life with impact drivers Manufactured with heavy-duty, cold-forged, high-grade steel to withstand high torque output Black oxide finish resists corrosion and increases life of bit