I know the ways to tell whether the polarized sunglasses are real. You may put two types of polarized sunglasses and put them in the up and down parallel position. If you see the things clearly through the two lenses, they are real. Then you put one sunglass in the vertical position for the other one. If you see nothing, they are real. The way is so easy. As we know, the polarized sunglasses can prevent your eyes from the strong sun lights which may damage your eyes. You could use the polarized sunglasses in driving or fishing which could do the special function for you.
Polaroid Sunglass lenses are manufactured using a polarizing sandwich method that employs a light filter in the center that is laminated on both sides with UV light absorbers. This filters out one-hundred percent of harmful UV, UVB and UVC radiation. The lens also has laminated optically corrected, shatter-resistant cushion elements and a scratch-resistant coating. If you are concerned about the authenticity of the sunglasses you are going to buy, you can ask for warrenty, certificate of production beforehand. Also, you could choose to call their customer service hotline to ask for help.