Customisable set, containing highly robust bits that are ideal for heavy duty applications. The screwdriver bits feature an extended torsion zone that makes them extremely sturdy for long lasting work, even withstanding the high power of impact drivers. S2 Modified Steel and an optimised heat-treatment process provide extra-tough endurance for high performance, including in-plant installations or heavy industrial work. HEX-9 multiconstruction drill bits are ideal for use in almost all materials, and feature diamond-ground cutting edges for high wear resistance and a 2-flute U-shape for good dust removal and standard lifetime. Their carbide tip provides an easy start and good control when drilling. Click-fitting slots enable easy replacement of old packs with individually purchased packs for a fully customised collection. All bits have a ¼" external hex shank and are suitable for use with drill drivers, screwdrivers, and especially with impact drivers.