Irwin Tools 1837412 Impact Performance Series TORX T40 Insert Bit These insert bits are built for maximum durability and long life with impact drivers Each screwdriver bit is manufactured with heavy-duty, cold-forged, high-grade steel These screwdriver bits can withstand high-torque output Precision-tip geometry on the insert bits delivers superior fitment with reduced stripping and cam-out A black oxide finish resists corrosion to help increase the life of each insert bit