How to distinguish whether sunglasses are UV-resistant? As we all know, the biggest feature of sunglasses is UV protection. An excellent performance sunglasses can achieve an ultraviolet protection rate of over 99%. Good UV protection is the key factor in our decision to buy sunglasses. Therefore, it is quite necessary to check the UV protection effect of sunglasses. Usually UV protection is 100% UV400. If there is no instrument to detect whether the sunglasses have anti-UV function, first take a hundred yuan, put the sunglasses lens on the anti-counterfeit watermark, and use the counterfeit pen or the money detector to illuminate the anti-counterfeit watermark on the lens. Seeing the anti-counterfeit watermark, it means that this sunglasses is not UV-proof; if you can't see it, it means that this sunglasses is UV-resistant.