Honeywell TS34C Long Range Temperature and Humidity Sensor for Professional Weather Station TE923W, White Indoor/outdoor temperature and humidity Indoor temperature range: 23-degree farenheit to 122-degree farenheit Outdoor temperature range: lithium batteries:-38-degree farenheit to 158-degree farenheit (-38.8-degree celsius to 70-degree celsius) alkaline batteries:-4-degree farenheit to 158-degree farenheit (-20-degree celsius to 70-degree celsius) Indoor/outdoor humidity range 20-percent to 95-percent 5 User-selectable transmission channels, transmission range of up to 328-feet (100-meters)