The REPTI ZOO Reptile Terrarium Hygrometer is a reliable and accurate way to measure humidity in your vivarium. With its dial gauge, you can easily monitor the humidity level in your tank. The hygrometer features different color-coded segments for easy reading, and the white side of the needle indicates when the humidity level is high. The REPTI ZOO Reptile Terrarium Hygrometer is easy to install and mount on most surfaces, making it a great way to keep an eye on the humidity level in your vivarium.