... on thermal measurement principal, using innovation, advanced, sensitive hot film sensor, strong pollution tolerance, low airflow angle dependence, easy to ... separately. See details on MMI product. SpecificationsAir velocityThermal hot film sensorrange0~5/10/15/20m/s or other (0~ ... factory calibration±(1% measuring value,min. 0.1m/s)Sensor temperature range-20~150°C,Temperature sensitivity <0.1%/ ...