Light reflected from surfaces like a flat road or smooth water is generally horizontally polarized. This horizontally polarized light is blocked by the vertically oriented polarizers in the lenses.

The result: a reduction in annoying and sometimes dangerous glare.

Besides boaters, drivers, and outdoor enthusiasts who benefit the most from polarized sunglasses include skiers, golfers, fishermen, bikers, and joggers, who enjoy a clearer view along with elimination of glare.