Monitor your reptile's habitat with this simple and inexpensive precision instrument. The Zoo Med Analog Thermometer and Humidity Gauge allows exact measurement of relative humidity as well as temperature, both parameters are crucial to your pet's health. Keeping an eye on environmental conditions helps to make sure your reptile stays healthy and happy. Now it's ultra easy and convenient to oversee exactly how humid and how hot it is so you can make any necessary adjustments within your terrarium.