Made of chrome vanadium steel With depth stop For flush driving in soft materials Prevents overdriving in plasterboard and plywood For use with a bit holder (available separately) or directly in a cordless drill or screwdriver 3 bits, 25 mm, 6.3 mm (1/4") male hexagon drive, PH2 cross head 3 bits, 50 mm, 6.3 mm (1/4") male hexagon drive, PH2 cross head