Accurate ReadingsWireless indoor outdoor thermometer provides accurate temperature and humidity readings for indoors and outdoors simultaneously. Precision : 1.1C and 2~3% relative humidity Cold-proof and waterproofThe weather thermometer with its fully sealed sensor contains a rechargeable lithium battery to control humidity and temperatures down to -35C, and provides transmission rain or snow Range up to 60mRemote thermometer measures temperatures and temperature percentages humidity up to 60 m/200 ft. Tracks environmental conditions of up to four locations using 2 additional remote sensors (need to purchase 2 additional sensors) InformativeBacklit touch screen displays temperature and humidity indoor and outdoor current, including trend arrows and max and min records, keeping you on top of changing conditions