Oakley has partnered with Transitions Optical to create lenses that darken and lighten automatically. The patented innovations of Oakley optics are blended with photochromic technology which actively tunes the amount of light that reaches your eyes. Even better, the lenses include base colors that precisely balance light transmission and boost visual contrast to improve depth perception. This unique blend of innovations gives you the ultimate in performance and comfort while improving safety in environments ranging from overcast to bright sun. Please note: These photochromic lenses are enhanced with performance base colors, so they do not fade to clear in the absence of sunlight. Also note that photochromic lenses darken in response to UV light, and car windshields block most UV.