DESCRIPTIONSimple yet stout in stature, the After Dark features a refined square frame made from lightweight swiss grilamid to provide the ultimate comfort. This is a great frame for long beach days or adventures into the wilderness, but can easily compliment you on those days where you need to button up. FEATURES Mineral Glass is created from natural elements like sand and soda ash. It’s endlessly recyclable and harmless to humans and animals alike. It’s high resistance to scratching and lack of distortion make it the world’s best lens material. It really does have to be Mineral Glass. All OTIS fixed-tint lenses block 100% of harmful UVA, UVB and HEV light to provide superior protection from solar damage causing intraocular melanoma and macular degeneration, as well as reducing eye fatigue and reducing the visible signs of ageing, while maintaing true color and depth perception. Lens 'Base Curve' is a measure of the front curvature of the lens. The higher the number, the greater the curve. 6 base lenses are generally flatter across the front. 8 base lenses have a greater curve for a more 'wrapped' look. High performance and low weight ratio. TR90’s high-performance property profile and processability makes it an ideal optical engineering plastic. The transparency, rigidity and impact strength of Grilamid compare favourably to other transparent polymers like polycarbonate. It is the lightest engineering plastic in existence, maximising wearer comfort. OTIS frames are produced with high quality 3, 5 and 7 barrel hinges. These premium grade Vissottica brand hinges are extremely durable and boast 100% corrosion resistance.