Fototec™ lenses with variable tint technology adjust rapidly to changing light conditions for superior clarity and protection. In bright sun, microscopic photochromic particles embedded in the lens react to UV rays, darkening the optics so you'll never squint. With cloud cover, the particles return to their previous state, letting through more light. Tifosi's Fototec™ lenses are market leaders because of their lightweight, durability and incredible speed. All Tifosi lenses offer 100% protection against harmful UVA/UVB rays.