Extech 445715 Big Digit Remote Probe Hygro Thermometer has a Probe that either clips on the meter or extends on an 18 inch cable. This meter has Max/Min storage capabilities with a clear function, and rear calibration adjustment pot. The ranges on this meter are: Humidity: 10 to 99% RH; Temperature: 14 to 140 degree Fahrenheit (-10 to 60 degree Celsius); Accuracy: +/-4% RH; +/-1 degree Celsius/1.8 degrees Fahrenheit.