Feautres: no batteries required (works on bimetallic strip) records the maximum temperature of the rainproof structure and can be hung for outdoor use 2 in 1 thermometer hygrometer 2 units: Celsius and Fahrenheit, °C/°F specifications: temperature measurement range: - 20 - 50 °C / 0-120 °F humidity measurement range 0 - 100% resolution resolution: 1 °C, 2% accuracy measurement accuracy, plus or minus 2°F +/- 5%, (40% - 70%) Product Size Unite Size: 128mm/5 inches Note: Item color displayed in photos may be showing slightly different when showing on your computer monitor since monitors are not calibrated same. Please allow 1-3mm slight deviation due to manual measurement. Thank you! Package Included: 1*5" Min Max Thermometer Hygrometer 1 * User Manual