Why You Need Them
ZZ Top may forever be remembered for its hits and "Cheap Sunglasses," but in reality, even that little ol' band from Houston, Texas, knew that when it comes to protecting your eyes, you don't skimp on quality. And since, as a boater, you spend a lot of time in the sunshine and dealing with the glare from the water, you need to be sure to treat your eyes right.

Sunglasses protect your eyes from ultraviolet radiation. Short-term overexposure to UV rays can cause photokeratitis (literally, sunburn of the eyes), and long-term overexposure can lead to macular degeneration, eye cancer and blindness. Shades also protect your eyes from wind and debris.

What You Need To Know
There are two types of UV radiation: UV-A and UV-B. Both are bad. Sunglasses should provide 100 percent protection against both UV-A and UV-B. Glass lenses are the strongest, but can shatter, so use a polycarbonate or shatterproof plastic lens for impact protection. Beware of low-quality lenses that can distort your vision. Before you buy, look through the lens at something with lines (like a tiled floor) and tilt, then move the glasses - if you see any distortion or waviness in the lines, put the glasses back, and move on to another pair. Thanks to their glare-reducing power, polarized lenses are generally recommended for all types of boaters, although they're especially popular with anglers because the polarized lenses allow them to see deeper into the water. Be warned that not all "polarized" lenses actually are. To test for polarization, find a horizontal object, such as a car hood or the water's surface, and look through the lenses from a few inches away. Slowly rotate the glasses 90 degrees. If the lenses really are polarized, you'll see the glare go away, and you can buy with confidence.

  The Final Word
It's important to avoid going out on the water without   a pair of quality sunglasses to protect your eyes. You don't have to spend a lot of money on brand names to get good quality - just make sure your shades provide  100 percent protection against UV-A and UV-B. Lens tint is usually a personal preference, but it's still a good idea to look for lenses that block at least 70 percent of visible light. You'll still see just fine with tinted lenses, and you won't have to squint.