EASY TO INSTALL Mini Digital Hygrometer Thermometer easily knows the current humidity and temperature, Embedded opening size (1.81*1.06 inch) or fixed with double-sided tape. High Precision Display Indoor Thermometer Hygrometer Temperature measurement accuracy: 1; Humidity measurement accuracy: 2%RH. WIDE TEMPERATURE TEST Indoor Thermometer Hygrometer Temperature measuring range -58-230 ; Humidity measuring range 1%-99%RH. Two in One Mini Digital Hygrometer Thermometer is 2in1 meter with built-in probe; digital electronic thermometer and hygrometer for measuring temperature and humidity for indoor use LONG BATTERY LIFE Hygrometer Powered by two LR44 button cell (Included), Battery working time up to 8 months. Package Includes: 4 x Digital Thermometer Hygrometer; 4 x Double-sided tape; Give away 4LR44 spare battery..