Note: The backlight function is designed to prevent sleep interference, so the display screen is dark, Please press the "LIGHT" button to turn on the backlight. After 8 seconds, it will automatically enter sleep mode again (the backlight will turn off) until you press the "LIGHT" button again Temperature measurement range: 0°C to +60°C (32 °F to +140 °F) Humidity measurement range: 20% ~ 99% Battery: 2xAAA (this product does not contain batteries) Relative humidity and weather conditions: Expresses in terms of relative humidity range: icons representing the sun, sun and clouds, clouds, clouds, and raindrops represent weather conditions: Sunlight: Relative humidity between 10% RH and 40% RH Sunlight and Clouds: Relative Humidity 41% RH and 65% RH Cloud: Relative humidity between 66% RH and 75% RH Clouds and raindrops: relative humidity between 76% RH and 99% RH