The 35-piece Pick and Clic Impact Control screwdriver bit set is very robust and designed for heavy duty use. The screwdriver bits have a special torsion zone that gives them extreme durability under continuous load, so that they can withstand even the high torque of impact wrenches. Impact Control HSS twist drills also provide solid drilling in metal, especially with impact drills. The oxidized spiral cutting edges and precision milled quality metal ensure less wear and excellent surface properties for drilling steel, iron and other metals. The bits have a 1/4-inch external hexagonal shaft. All bits have a 1/4-inch external hex shank for use with drill bits, screwdrivers and especially impact wrenches. This set is part of the Bosch Pick and Clic system, which allows customizable accessory sets for completely flexible bit collections. Pick and Clic inserts secure individually purchased bit packs for individual collection and easy replacement of old bit packs.