4-stage switch for hum-free control of non-ECO ceiling fans. The controller works with microcapacitors. Degree of protection IP44. Supplied with a surface-mounted housing, installation in standard flush-mounted boxes is possible. As a special feature, the ST4-150 II can be integrated into any switch system with a 6 mm axis using the rotary knob, the frame and the central cover plate of the third-party system. A separate dimmer or switch is used for ceiling fans with lights. Motor max. 100 watts.