Built to withstand extreme nautical environments. And float in them. We suggest you keep them on board, but we've made our Marine series binoculars buoyant, waterproof and corrosion resistant, so a little dunking won?t deep-six your day. You'll appreciate the ultra-bright, crisp views through their multi-coated optics and premium BaK-4 prism glass. Rugged rubber armoring provides a sure grip, absorbs shock and keeps them from sliding in rough conditions. They're essential equipment if you spend much time on deck, and aren't fazed by a little time off it.