Waterproof (up to 1m/3.3 ft. for 10 minutes) and fog-free with nitrogen gas High-eyepoint design provides a clear field of view, even for eyeglass wearers Multilayer coated lenses for brighter images Turn-and-slide rubber eyecups with multi-click facilitate easy positioning of eyes at the correct eyepoint Eco-glass optics that are free of lead and arsenic are used for all lenses and prisms