The ErgoStar holder means you will never have to fiddle to extract a key from the holder. Rotating a single key means all the other keys rotate to the side, presenting all 13 keys for easy removal. The keys themselves are chrome-vanadium steel, through hardened and chrome-plated. The innovative MagicRing® is a spring steel ring on the ball end, which grips the head of the screw and gives trouble-free insertion and removal of the screw. The hex key in effect becomes a handle with the screw held securely on its tip. The ball end allows the key to operate at up to 25° from the vertical, very useful in awkward corners. The 13-piece imperial set covers the size range from 0.05" to 3/8". Please note that the five smallest sizes in the set are standard ball hex keys, being too small for a MagicRing®.