Jumbo display. Rotating head to protect sensor. Field calibratable. Auto power off. Min/max. Displays temperature, humidity, dew point, wet bulb. Temperature range: -4 to 122 F (-20 to 50 C). Humidity: 0 to 100 percent. Dew point: -90.4 to 122F (-68-49.9 C). Wet bulb: -69 to 122F (-21 to 49.9 C). Temp. accuracy plus/minus 10 F (plus/minus 0.6 C). Resolution: 0.1 degrees; 0.1 percent RH. Response time: 60 sec. Optional probe available (number P8706). Includes two AAA batteries.