Any set of sunglasses should shield your eyes from UV radiation as stated by law. While different tints of lenses may let through different amounts of visible light, darker lenses don't always provide more UV protection. All sunglasses will provide you with a minimal amount of protection, but it is always wise to wear lenses that will keep you safe compared to the UV rays you will be exposed to. Therefore, if you're worried, check the producers' specifications for further information.