The Extech RH200W Multi-Channel Wireless Hygro-Thermometer displays easy-to-read 1.3 inch (33mm) digits that show indoor temperature and humidity levels. Up to 8 wireless transmitters can connect to the main unit to remotely measure Temperature/Humidity levels up to 98 ft. (30 m) away. The LCD is designed with an auto-night light, and it displays icons that indicate indoor comfort levels and trending arrows that show the increase, decrease or constant readings. It also records Min/Max readings for the duration of each measurement session.