Long Distance Transmission Wireless Thermometer Hygrometer with 3 Outdoor Sensors 433Mhz Frequency, you can place three sensors waterproof Ip54 in different positions. Their data will be displayed on the same screen without frequent channel selection. The distance between the host and the sensor The transmission distance is 300 feet91M long without obstacles or walls, and the effective transmission distance is up to 100 feet30M with obstacles. White backlight and smiley display The LCD screen shows clear arrows, you can see temperature and humidity changes at any time. The backlight will automatically turn off after 8 seconds without any setting. The smiley symbol meansWet comfortable dry. Indoor temperature 050C32122FOutdoor temperature 50C70C58F158F, Humidity 2099. Temperature and humidity accuracies are within 1C5. Temperature and humidity calibration and alarm function When the humidity and temperature reach the maimal or preset minimum, it will sound and the backlight color alarm backlight changes to red and orange. If the temperature and humidity are outside the normal error range, you can manually correct the error by pressing the TimeSet button. 5 buttons Our hygrometer thermometer can record temperature and humidity over time, MinMa button can display all temperature and humidity Maimaltlitet value data, long press can delete previous data and rerecord. CThe F button can switch between Celsius and Fahrenheit. In addition, there are alarm settings for time 1224 hour format, date and upper and lower limits for temperature and humidity. USB powered The remote thermometer has two power supply methods, battery not included and USB cable power supply, easy to use, no need to worry about battery replacement including USB cable. The thermometer can be hung through the hanging base hole. Very convenient to use. The three sensors have hanging holes on the back, which can be easily hung on the shelf.