I often get asked what the difference is between ordinary UV400 sunglasses and polarized sunnies. I usually show people how polarized sunnies work by placing lenses over each other, rotating them and showing customers how they go black.
What's actually happening is that light is only allow to pass through the lens in one plane (or direction). This reduces the amount of reflected light entering your eyes and reduces glare.
Polarized sunglasses are particularly useful for fishing because they take the shimmer of the surface of the water allowing you to see deeper into the water. They are also recommended for really bright situations such as around water or in the snow.
UV400 sunglasses block 99.9% of dangerous UV radiation. You need to look at the sunglasses you are purchasing and check that they meet the Australian Standard - AS/NZS 1067:2003 and that they are marked UV400 or 100% UV Protection.
All of the sunglasses we sell are UV400, whether they are polarized or not.