Pawliss Digital 2-in-1 Terrarium Reptile Thermometer Hygrometer With Probe Fast and accurate temperature and humidity readings. Display in Fahrenheit. With a probe so you can put it any place you want Small and convenient Size:2" x 1" Range: -58F ~ 210F humidity 1% ~ 99% Power source: 2 x LR44 button cell (Batteries NOT included).