Nocs Zero Tube Waterproof MonocularMade for exploration, the Zero Tube monocular from Nocs is rugged, compact, and capable. It has multi coated, extra low dispersion optics that reduce reflections while enhancing color and contrast, with a twisting eyecup that extends or retracts as needed and nitrogen filled chambers to ward off fog. A ribbed non slip grip helps keep things in hand, but its IPX7 waterproof rating means it can withstand a drop or two should it slip away.