The AcuRite Wireless Temperature/Humidity Sensor has a built-in thermometer and hygrometer to measure indoor or outdoor environmental conditions with precision and accuracy. The sensor features a compact size weather-resistant design and integrated mounting options. The sensor can wirelessly send its readings up to 330 (100 meters) to compatible AcuRite thermometers multi-sensor stations and weather stations or it can be paired with the AcuRite smartHUB allowing you to monitor your sensor information from anywhere in the world using your smartphone computer or tablet. The wireless temp/humidity sensor requires two AA batteries not included. Wireless remote temperature and humidity sensor. Compatible with AcuRite thermometers multi-sensor stations and weather stations. Can also be paired with the AcuRite smartHUB. 330 wireless range. Requires two AA batteries not included.