Dewalt dt70580 extreme impact screwdriver bit set 42 piece is suited to impact screwdrivers and drill drivers alike with all the common sizes and a pair of dewalt safety glasses this is a perfect starter set for the professional trades supplied in a small robust tough case for safe storage and easy accessibility to screwdriving and nut setting accessories the bits feature a hex shank design with a heat treated body and an optimised tip design giving increased strength life and durability the acc