Universal Use - The Extra Hard Screwdriver Bit Set, 35-Piece is a good choice for universal use. This complete set contains accessories for important drilling and screw-driving applications. The screwdriver bits are composed of S2 Modified Steel and an optimised heat treatment process, which provides an extra-hard quality that delivers a strong performance for all tasks. All bits are colour-coded for quick viewing and identification of the appropriate bit type. Furthermore, the set contains HSS (high-speed steel) drill bits for precise results in soft and hard wood. These extremely sharp drill bits with a centring tip allow for accurate hole positioning. They have a 1/4-inch external hex shank for use with screwdrivers and drill drivers. The drill bits feature cylindrical shank systems for all corded or cordless impact drills. The Extra Hard Screwdriver Bit Set, 35-Piece comes in a practical and robust storage box providing a good view of its contents as well as safe storage and transp