Photochromic lenses are specially treated to turn dark when exposed to UV light. When the lenses are out of the sunlight, they become clear again. If you want to order Transitions®, you can choose Photochromic lenses on our website.
We carry photochromic lenses for 1.57, 1.61, 1.67 and 1.71 lenses for single-vision glasses. And 1.57, 1.61, and 1.67 lenses for progressive glasses.