The Pyle PMA90 is a digital anemometer and thermometer. This meter uses conventional angled vane arms with low-friction ball bearings and an NTC-type thermostat for accurate, speedy readings (1/sec). It measures air velocity, air flow and temperature. It measures velocity in m/sec, km/h, ft/min, mph and knots also measures air flow in CMM and CFM. The PMA90 automatically powers off after 20 minutes to save power.