Extech AN100 CFM/CMM Mini Thermo-Anemometer Large display of airflow or air velocity Simultaneous display of air flow or air velocity plus ambient temperature Easy to set area dimensions (cm2) are stored in the meter's internal memory for the next power on 20 point average for air flow 3-percent velocity accuracy via low friction 2.83-Inch D (72mm) ball bearing vane wheel on 3.9-Feet (120cm) cable