Built to provide technically advanced eye protection to enthusiasts of all sports and outdoor activities, Tifosi Duro sunglasses with interchangeable lenses are guaranteed to enhance your sport whether you're running a 10k, riding a century, or heading out on the weekend for a kayak fishing trip.Grilamid TR-90 frame offers an extremely high alternative bending strength, low density, and high resistance to chemical and UV damage. Includes three sets of lenses:~ Smoke Red lenses provide 15.4% L.T. (light transmission) and provide good contrast~ Smoke Bright Blue lenses provide 11.2% L.T. and are great in cloudy conditions~ Clear lenses provide 95.6% L.T. and allow the user to have eye protection at night or in other extreme lowlight conditions. Lenses are made of scratch-resistant, shatterproof polycarbonate; Smoke Red lenses feature proprietary Glare Guard lens coating. Optically decentered lenses eliminate distortion and prevent distracting magnification. Lenses are vented for increased air circulation to prevent fogging and keep you cool. Hydrophilic rubber nose pad and earpieces ensure a non-slip fit. Adjustable temples and nose allow for customizable comfort. All Tifosi sunglasses provide 100% UVA/UVB protection.