These are the sunglasses that use optical technology developed by NASA to improve visual clarity and fold for convenient storage. Based on technology designed by NASA’s Jet Propulsion Laboratory to protect astronauts’ eyes from solar radiation, the lenses block blue and violet rays that impair vision yet allow sight-enhancing green, yellow, orange, and red rays to reach the retina. A hinge hidden on the inside of the bridge folds the frames in half, enabling unobtrusive storage in a shirt pocket. The sunglasses block 99.9% of harmful UVA and UVB rays while making objects appear more distinct and diminishing distortion. Both sides of the lenses are covered with two layers of a scratch-resistant coating, the frames are made from durable polycarbonate, and the included leatherette case provides protection when the glasses are stored. Tortoise or Black frames. 5 1/2" W x 1 1/3" H. (1/4 oz.)