While not the first to come up with Concrete Eyewear, this are certainly the latest by XYZ Integrated Architecture. I couldn’t imagine how heavy and uncomfortable it would be to wear these. Since there was only one made, will not have to worry. The front was poured into a silver mold and the temples appear to be from some sort of plastic or acetate. With a bowed top brow and unusual shape, these sunglasses, are not for the light weight.