The compact vane anemometer testo 417 is designed to facilitate measurement at inlet and outlet grilles of air conditioning and ventilation systems. The built-in 100 mm vane probe ensures fast and precise results when measuring air flow velocity. The time and point averages as well as the flow rate are automatically calculated in the device and visualized on the display. This allows efficient setting of ventilation systems in residential buildings. In addition, the testo Smart App not only supports you in configuring the measuring device, but also visualizes, stores and documents the measured values. In addition, it turns your smartphone into a second display. The testo 417 is also available in two practical sets: Testo 417 set 1, which includes two measuring funnels for round outlet openings and ventilation grilles. Funnels can be easily fixed to the vane probe and are suitable for different sized grids. In addition to the two measuring funnels, the testo 417 set 2 includes a flow rectifier to achieve precise results even in the presence of turbulence in the air duct.