This 11-in1 Extech EN100 Environmental Meter is a multipurpose meter that is capable of measuring 11 different environmental factors. These factors include: Air velocity, air flow, temperature, wet bulb, humidity, dew point, wind chill, heat index, altitude, barometric pressure, and even light level. This pocket-able unit features an easily replaceable mini-anemometer vane for field repair and a backlit LCD display.