Nikon EDG 10x42 Waterproof / Fogproof ED Edge Binoculars 7562 is a binocular for those whose adventurous spirit and dedication to success demands performance above all else. The most dynamic and advanced binoculars in the company's history, the Nikon EDG (pronounced "edge") was engineered using Nikon 's latest cutting edge technology, refined by nearly a century of glass-making heritage. Nikon EDG binoculars feature an optical system that incorporates 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 42 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. These Nikon binoculars include the ergonomically contoured horn-shaped eyecups preferred by some hunters prefer for blocking out peripheral light from the eyepieces. The eyepiece included with each Nikon EDG binocular is a quick-detachable style to accommodate both points of view.