Serengeti Nunzio Sunglasses, Crystal Photochromic Brown/Polar PhD Drivers Lens Medium/Large fit, Universal The amber-colored Drivers lens amplifies contrast and definition, delivering vibrant colors in all environments Our photochromic technology works by embedding molecules within the lens to constantly adjust to changing light conditions By managing colors within the visible light spectrum, Spectral Control technology gives you stunning, high-definition contrast and color enhancement Serengeti's polarization technology is specifically engineered to eliminate distracting glare, giving the wearer unsurpassed clarity and comfort