With temperature display ACTUAL value Automatic controller calibration Switching contact opens when the set temperature is reached. With spreader fastening With separate connection for time-controlled night-time reduction (4K). Class of temperature controller: 1 Contribution to room heating energy efficiency: 1.0%. Only in conjunction with commercially available flush-mounted device boxes in accordance with DIN 49073, install or Busch-Jaeger item no. 3040 flush-mounted box masonry, 3050 flush-mounted box hollow wall or 3060 flush-mounted box concrete) Control valves in the de-energized closed version are required for the controller. E.g. item no. 6164/10-102. Switching temperature difference ± 0.5 K.