If you're not the type to be using binoculars from the comfort of your own home, you know they'll be coming into contact with some of the rougher elements out there. Including water. Water can wreak havoc on regular binoculars causing rusting and lens fogging so they'll be damaged beyond repair. So get some heartier wilderness binoculars that are waterproof, even fog proof. So you can keep looking at whatever it is you're looking at out there in the wild world.
Prisms
Waterproof binoculars can be entirely submerged in the water because the should be totally sealed from letting any water in. That's your own consumer product test. You just have to decide if you're looking for compact waterproof binoculars or if the type of image you see is more important. For example, porro prisms are better for star-gazing because they present a more realized, brighter image of what you're magnifying. But these prisms make the binoculars a bit clunkier. Roof prisms let you see just as much, but perhaps in a less fancy way, and allow for the binoculars to be smaller and lighter.
Lens Coating
To let the most amount of light in and to reduce glare, you'll want lenses that are at least multicoated lenses. The fog proofing comes from the binoculars being filled with nitrogen gas that keeps them from letting any dampness permeate even in wet conditions.
