High performance metal drilling for portable drill users, works well on curved surfacesRevolutionary tip design stays sharper longer and drills up to 10x faster than other leading drill bitsHigh speed steel features a black body and gold fluteSelf-centering TURBOMAX tip for clean entry and fast starts; stays sharp longerThree flatted shank on 3/16" and above for better chuck grip Size: 5/16" Twist Length: 3-3/16" Overall Length: 4-1/2"