18mm Ultra Short 1/4' Hex Screwdriver Bit Set Cross Slotted Torx Hexagonal Electric Screw Driver with Magnetic Hand Drill Bits Specifications Materials: S2 alloy Steel Type of head: Hex/Phillips/Slotted/Torx Overall length: 18mm Type of shank: 1/4' 6 T5-T40 H1 PH1 PH2 PH3 SL6