Anti-corrosive spring that provides flexibility offering a secure, comfortable fit for various face shapes and sizes All Maui Jim sunglasses feature PolarizedPlus2 lens technology that go beyond shielding your eyes from glare and harmful UV rays by enhancing colors to reveal the true beauty of the world around you Enjoy ultimate UV protection combined with premuim style, incredible durability, glare-free vision, and color-boosting patented technologies Neutral Grey lenses offer the highest available light reduction and are most useful in bright, direct sunlight Frames constructed from lightweight, injected nylon, designed for extreme comfort and extended wear time