Description:1. Type: Electronic thermometer and hygrometer2. Low temperature alarm (the temperature will be lower than the preset value will give an audible alarm).3. Indoor temperature range: 0 °C to +60 °C.4. Outdoor temperature range: -40 ° C to +60 ° C.5. Accurate temperature: 1.06. Power supply (host): 2x7 battery7. Power supply (slave): 2x5 battery8. Wireless range: no interference 100 meters

http://olla.gr/home-wireless-refrigerator-thermometer/