Extech EN150 Compact Hygro-Thermo-Anemometer with UV Light Sensor Sensors measure Air Velocity, Air Flow, Temperature, Humidity, Wet Bulb, Dew Point, Heat Index, Wind Chill, Barometric Pressure, Altitude, UV Light Field replaceable low friction vane wheel improves air velocity accuracy Backlit LCD display (auto off after 5 seconds) Data Hold, Auto Power Off, Auto-rotating display depending on function Complete with built-in multiparameter sensors, wrist strap, and CR2032 battery