For a reliable optical performance, get the Nikon Action Ex Extreme binocular. The all-metal chassis of this Nikon 10X50 Binocular has the lens fitted into an extremely lightweight polycarbonate body shell. This Nikon binocular can be used in any environment as it is nitrogen filled and o-ring sealed that makes it waterproof, fog proof and shockproof. The rubber coating of the Nikon Action Ex Extreme binocular offers a non-slip grip, even when it is wet. This Nikon 10X50 Binocular has a central focus with a diopter control that corrects the eye-vision imbalance and hence delivers a strain-free viewing experience. The 17.2 long eye relief in this Nikon binocular helps the eyeglass wearers to have a perfect viewing experience.