Nikon 10x32mm EDG Waterproof / Fogproof ED Binoculars Edge 7564 is a high-performance binocular for those with an adventurous spirit and a dedication to success. Nikon EDG (pronounced "edge") is the most dynamic and advanced binoculars in the company's history. These Nikon binoculars were engineered using cutting edge technology, refined by Nikon 's hundred-year history of glass-making. Nikon EDGE binoculars sport an optical system with phase-correction coated roof prisms to enhance resolution, as well as dielectric coated sub-prisms to maximize light transmission. Interacting with fully multicoated lenses and ED glass, the high-grade prisms deliver extremely bright, clear, vivid images across the periphery of the viewing field. To further enhance viewing pleasure, these hunting binoculars have a thoughtful and convenient dual-phase central focusing knob provides both precise focusing and diopter adjustments in the Edge 10 x 32 binocular. This single, multifunction control locks the focus when diopter correction is necessary for unparalleled speed and convenience, yet discreetly integrates it within the central focus knob itself for understated style. Ergonomically contoured horn-shaped eyecups block out peripheral light from the Nikon EDG Binocular eyepieces, in a quick detachable style with that gets them out of the way when not needed..