The AET-961 is a hot wire thermo anemometer, it is ideal for low air velocity and volume measurement. The slim plug in telescopic hot wire probe extends from 0.26 to 1.2m (inc handle) has a probe sensor head 8.5mm and is ideal for grille hoods and diffusers. It is excellent for ventilation surveys, air conditioning, clean rooms, flow hoods, air balancing and environmental monitoring.0.1 to 35m/sec x 0.01Measures air velocity in m/sec, ft/min, km/hr, knots or mphMeasures air volume in m3/min or ft3/minMeasures temperature C or F55mm LCD display with backlight and function indicatorsData hold and min/max hold for airflow and temperatureLow battery indicatorAuto power off after approx. 20 minutes of inactivity can be user disabledAverage calculated from the last 10 airflow readingsStandard " camera bush for tripod mountingSupplied with hard carry case, telescopic probe, AC/DC power adaptor and batteryNote: This instrument operates on the basis of maintaining the sensor element at a constant 80C. Therefore, the battery life is limited to approx. 4 hours operation.