The Extra Hard and Metal HSS Set, 35-piece, is a comprehensive Pick and Click set for all standard screwdriving and drilling tasks in metal. It includes all the standard accessories you need for screwing and effective drilling in metal. The screwdriver bits are made from heat-treated, S2-modified steel for hardness and wear resistance. They are color-coded to help you easily find the right bit. With the durable Metal HSS drills included in the set, you can drill into metal. Their cross-ground tip allows for precise starting. The set is housed in a sturdy Pick and Click case, so you can assemble your own toolbox and keep your bits well organized and protected. The screwdriver bits have a 1/4" hex shank for use with three-jaw chuck drill drivers and hex drill chucks. The drills feature a cylindrical shank that is compatible with three-jaw drill chucks.