Silicon Solar UV Tester key holder check the level of Solar UV radiation with the level of low, moderate, high or very high/extreme.

the Silicon Solar UV Tester key holder can change colors according to Solar UV radiation, higher the Solar UV radiation, deeper the color change, compare the color change to the 4 standard colors (low, moderate, high, very high/extreme) around and you can see low, moderate, high or very high/extreme level of Solar UV radiation;