Temperature measuring range: -50? 70?(-122? 158?) Temperature measuring accuracy: 1? (at normal temperature) Humidity measuring range: 10 99 RH Humidity measuring accuracy: 5 RH Sampling period: 10 seconds Rated voltage: 1.5V Battery: 2 LR44 button batteries Diameter: 1.8 inches Install: use a double side tape to paste the thermometer inside the terrarium. Note:Due to the lack of battery power, sometimes the value may be incorrect. Replace the battery at this time. If you have any questions, please feel free to contact customer service.Due to the lack of battery power, sometimes the value may be incorrect. Replace the battery at this time. If you have any questions, please feel free to contact customer service. Temperature measuring range: -50? 70?(-122? 158?) Humidity measuring range: 10 99 RH. Switchable Celsius and Fahrenheit Degree. Thermometer and hygrometer combination. Small size digital LCD display.