100% UV Protection. Grilamid® is a nylon compound that when heated and mold injected becomes a light, strong plastic material. Once grilamid® is formed, it has the amazing attribute of being extremely flexible, while still maintaining its original shape under all temperatures. 6 Base Polycarbonate Lens. 5 barrel stainless steel hinge. Large fit. Grey - Light transmission: 10-15%. Most popular color for general purpose sunny conditions. Colors remain true with no distortion.