Feature: 1. Hour, minute, second, temperature and humidity, and analog time are displayed on the same screen 2. Two sets of alarm clocks 3. Snooze function, the default is five minutes 4. Countdown function 5. Countdown dynamic progress bar indicator circle 6. Countdown dynamic back second indicator circle 7. Indoor temperature (measurement range: 0℃~ 50 ℃/32℉~122℉), refresh time: 30 seconds. Resolution: 0.1 ℃. 8. Indoor humidity (measuring range: 20% ~ 99%) refresh time: 30 seconds. Resolution: 1%. 9. Maximum and minimum indoor temperature and humidity 10. Set indoor temperature and humidity over-limit value 11. Temperature and humidity over-limit warning Color backlight prompt 12. Temperature and humidity calibration function 13. Waterproof rating: IPX4 2. Power supply mode: 1. USB DC power cord power supply (when the DC power cord is plugged in, the backlight will be on for 8 seconds, when no buttons are operated, It will go out automatically. If you need to keep the backlight on, you can press and hold the 【CLEAR】 key for more than 2 seconds, and turn on the always-on backlight state after Bi beeps. If you need to turn off the long light, long press the [CLEAR] key for more than 2 seconds, and turn off the backlight after Bi beeps. During the countdown operation and alarm period, the backlight is always on regardless of whether the DC is plugged in or not). 2.3 AAA battery power supply (when the battery is powered, the product cannot always be on). Note: The product is shipped without batteries.