Ideal set for climate professionals focusing on volumetric flow measurement. You will receive the universal climate measuring device testo 400 with intuitive measurement menus, a hot wire probe head (including temperature and humidity sensor), a vane probe head (Ø 100 mm), and a highly precise humidity-temperature probe head – all three can be attached to the included Bluetooth handle. For measurements at ceiling outlets, simply combine the 100 mm vane probe with the telescope (extendable up to 1.0 m) and the 90° angle.