1. Time display: The default display of the clock when it is turned on is AM12:00 2. The 12-hour system and the 24-hour system can be switched, and the default is 12-hour system 3. Calendar display: The default display when it is turned on is January 1, 2020 AM12:00; the default date display format is: M-D 4. There are 8 countries in the week language, and the setting order is: EN (English) --- (German) --- IT (Italian) --- FR (French) --- NE (Dutch) --- ES (Spanish) --- DA (Danish) --- RU (Russian), the default display when it is turned on is: EN (English) 5. Indoor temperature display: 0C-50C (32F-122F) Error: 1C Indoor humidity display: 20%-99% Outdoor temperature display: -50C-70C (-58F-158F) Error: 1C Outdoor humidity display: 20%-99% Temperature units can be switched: C/F Default display unit: temperature [] Indoor and outdoor temperature and humidity maximum/minimum value recording Indoor temperature and humidity upper/lower limit over-limit sound alarm prompt Indoor temperature and humidity upper/lower limit over-limit backlight color alarm prompt: orange-yellow backlight prompts temperature and humidity upper limit; red backlight prompts temperature and humidity lower limit Outdoor three-channel temperature and humidity data are displayed on the screen Temperature and humidity calibration function Wireless transmission distance: open distance is 100 meters Screen size: 4.72 inches This product does not come with batteries. You need to bring 3 x AAA batteries to power the receiver and 6 x AAA batteries to power three transmitters. Due to different factory batches, the product words are different, and the product accessories have slight differences in color and appearance, but it does not affect normal use Colour:As Shown Material:ABS Package Contents: 1set x wireless indoor and outdoor digital thermometer and hygrometer Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.