The high-performance measurement transmitter testo 6621 is a reliable partner for applications in building air conditioning. Accuracy, long-term stability and reliability – our measurement transmitter meets the high demands of building automation, helping you to reduce costs.

In combination with the testo 660x probe series, the testo 6651 temperature and humidity transmitter meets high demands in air conditioning technology. Testo's temperature/humidity transmitter is even impressive where the climate is critical. This is because it enables a high level of measuring accuracy and the measurement of higher temperatures (up to +120 °C).

The testo 6631 temperature and humidity transmitter is ideally suited for use in greenhouses and laboratories. Use the transmitter for the reliable monitoring of critical climates in bio research.

The testo 6681 temperature and humidity transmitter is designed for monitoring critical climate in industrial processes (e.g. production/process engineering). If these involve maximum precision or specialized applications (high humidity, trace humidity, etc.), then this climate transmitter is the ideal choice because, when it comes to humidity measurement, it features unrivalled cutting-edge technology.