Optimally adjusted air conditioning and ventilation systems are a decisive factor for modern buildings. It is therefore important to use a suitable measurement technique to ensure that the air flow rate, temperature and flow rate in the ventilation duct are correctly measured. The testo 425 thermal anemometer is your quick, easy and precise assistant. The cable-connected telescopic probe can be extended up to 820 mm, making it easier to work on hard-to-reach objects on the ceiling or in large-diameter air ducts. All calculations, such as flow rate or time and point averages, are performed automatically by the robust and compact meter. Configuration of the measuring device, visualization and storage of measured values are carried out using the testo Smart App, which turns your smartphone into a second display.