The Klein Tools QRST01 13-Step Drill Bit features dual spiral flutes that helps pull the step bit through the material for faster cutting. An aluminum titanium coating provides added durability for longer bit life. The 1/4 in. hex shank provides a firm, positive grip and allows quick and convenient usage with an impact driver and a drill. Users are provided with thirteen hole sizes ranging from 1/8 in. to 1/2 in. with laser marking for easy identification.