The OTIS Non Fiction Sunglasses Are sun protection and a statement all rolled into one. Frames that stand out, starting out with an acetate frame and featuring a metal bridge and brow bar. Driving around with the top down or rolling right into the city, let the sun shine bright. Eyes stay protected behind mineral glass that has been tinted to block UVA, UVB and HEV light. Features of the OTIS Non Fiction Sunglasses Mineral Glass: 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 100% UVA/UVB Protection: 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 aging, while maintaining True color and depth perception 6 Base Lens Curve: Lens 'Base Curve' is a measure of the front curvature of the lens, 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 Handmade Acetate Frames: Made with premium quality acetate (originating from renewable resources Wood pulp and cotton fibre) the ideal material for making durable eyewear, Its hue is embedded within the product rather than sprayed onto the surface, retaining color brightness and preventing peeling and fading, OTIS handmade frames have stainless steel wires injected into the temples for adjustability - a task best performed by an Eye CAre Professional Vissottica Hinges With Stainless Steel Screws: 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 Sizing: 46.5 - 21 - 50.5 (mm)