It’s National Sunglasses Day. It's enough of a thing there's even a Snapchat filter for it.

And while you might be thinking, “seriously, who cares about sunglasses day?”, the answer is, you should. While some people wear sunglasses for style, they're really to protect your eyes from UV rays which can cause cataracts and other vision loss.

Here's the question, “Do more expensive sunglasses have better protection?”. A few years ago CBS bought 33 pairs and had them tested.

“If this machine reads zero, then it means our glasses have 99 or 100 percent protection,” says Opthamologist Marc Werner.

The $100 sunglasses test perfect. So do the $55 glasses. But what about the glasses bought on the street and at the drugstore?
They were perfect too.

Only one pair of the 33 didn’t test perfect. So chances are, those cheapie glasses you bought are just fine.