Tekton bits are 30 mm long to improve your access to recessed fasteners, as opposed to the standard bit length of 25 mm. The bits are made of S2 steel and have a zinc-phosphate coating that resists corrosion. The tip size and Tekton "T" are clearly stamped onto every bit in the set for easy identification. The bits can be stored in the included rubberized bit rail that securely grips the bits so they can't fall out, while also making it easy to remove any bit one-handed.