The EN100 is a Compact Hygro-Thermo-Anemometer with Light Sensor. 11-in-1 Environmental Meter for indoor and outdoor conditions. Built in light sensor measures light level. Auto-rotating display depending on selected function. Also measures Air Velocity, Air Flow, Temperature, Humidity, Wet Bulb, Dew Point, Heat Index, Wind Chill, Barometric Pressure and Altitude. Complete with built-in multiparameter sensors, wrist strap, and CR2032 battery.