The Helios TME 4 is an electronic four-step thermostat with a 1 K switching interval relative to the set target temperature. It supports integration with the KTR climate regulator to provide 5‑stage fan speed control that operates independently of the selected nominal or actual temperature. The thermostat is housed in a robust, shock-resistant polymer enclosure with a light grey finish and IP54 protection rating. Cable entry is positioned at the bottom of the unit via a PG 11 gland for secure and convenient installation.