These performance lightweight lug nuts are made from extremely strong and lightweight Duralumin. They are less than half of the weight of most stock lug nuts. One feature that make these lug nuts unique is that they come with one 7-sided locking type nut per wheel. These heptagonal lug nuts look stock from distance but can only be taken off with a special key that comes with the set. This is a great way of protection to your precious wheels. Anodized finish available in red, blue and black. Hex size for lug nuts is 19mm. The outer diameter of the key is 26mm. Make sure the holes on your wheels are big enough to fit the lock key. In most cases, if you have wheels of tuner styles and require smaller diameter lug nuts, then this set will not work.