1.0 series of Northug lenses. The Photochromatic lenses automatically adapt to the light conditions and change in step with them. With a lot of sun and bright light, the light input is reduced and the spectacle lenses become darker. Similarly, in darker light conditions, the lenses let more light through and become brighter. The lenses are hydrophobic & water repellent and provide maximum protection against the elements. They are made of fracture-resistant polycarbonate with Anti-Fog treatment. Fits Gold glasses..