These Engage DX binoculars from Bushnell are the perfect combination of performance and capability. They have 12x magnification with 50mm objective lens diameter and BaK-4 Prism glass. The roof prisms are dielectric coded for high resolution viewing, and the IPX7 waterproof design guarantees that they'll never fog up. The binocular’s EXO barrier bonds to the lens and repels water, oil, fog, dust, debris and more, while the all-metal chassis supports superior ruggedness. Close focus: 8ft. Exit pupil: 4.2mm. Eye relief: 18mm.