The Silva Echo Binocular 10 x 25 is designed for outdoor use, sports, travelers and hikers. The double hinge system makes this pair of Silva binoculars fold down to a compact and easytocarry format when not in use. Waterproof and Nitrogen filled ensures many years of troublefree use in varying conditions. Silva Echo Binoculars offer great optical performance with the Bak4 optics.