The 45170CM is a convenient 5-in-1 Environmental Meter which measures Air Velocity, Air Volume, Humidity, Temperature and Light. Ergonomic housing design with a large dual "smart" LCD where characters on display reverse direction depending on the function in use. This multi-functional meter is ideal for professional or home use in testing the environmental quality in a building. Featuring Data Hold, Min/Max, Auto Power Off functions. Complete with built-in sensors, wrist strap and 9V battery.