Here is the English translation for the description and features of the testo 440 measuring instrument:

---

3 AA batteries, USB cable, and factory calibration protocol

• Intuitive operation: Clearly structured measurement menus for measuring volume flow, degree of turbulence, cooling/heating output, mold detection, and long-term measurements such as CO
  2
  ​
  measurement
• Convenient and compact: Bluetooth® probes for added convenience during measurement, storage, and transport (probes ordered separately)
• Clear data display: Large graphic display with three rows of measured values
• Convenient saving and processing of measured values: Internal memory and USB port for data export
  Accurate and efficient measurement of all velocity and indoor air quality parameters with just one measuring instrument: a multi-functional measuring instrument with intuitive operation and clearly structured measurement menus. Setting up air conditioning and ventilation systems, controlling air quality, or measuring comfort level – thanks to interchangeable, high-quality digital probes, you are perfectly equipped for any measurement task (probes ordered separately).

You can use the testo 440 instrument in combination with high-quality probes for measuring velocity and assessing indoor air quality (probes ordered separately). Up to 3 probes can be connected simultaneously: a Bluetooth probe, a wired probe, and a temperature probe with a Type K thermocouple connector. Automatic probe detection and clearly structured measurement menus will simplify your daily work.