With rotary handle/push button switch. Only install in conjunction with commercially available flush-mounted device boxes in accordance with DIN 49073, Part 1, or Busch-Jaeger item no. 3040 flush-mounted box for masonry, 3050 flush-mounted box for hollow walls or 3060 flush-mounted box for concrete. These blind switches/buttons prevent the direction of travel from changing too quickly. Version: 1-pole, N, E Design: flush-mounted