It has an outer hex shank size 1/4-inch for general screwdriving work with screwdrivers and drill screwdrivers. This Extra Hard screwdriver bit is a good choice for general work. S2-modified steel and an optimised heat treatment process result in above-average hardness for adequate performance in all kinds of work. The bit's tapered torsion zone handles torque peaks well as it absorbs forces and vibrations during screwing. This enables it to cope with all kinds of work.