The CK push button family is characterized by a wide range of possible combinations: various circuit diagrams, touch surfaces, front panels, LED colors, pictographs and tactile symbols. A variety of light and sound signals are available to suit your specific requirements. An hourglass effect display is another option in order to indicate waiting times in front of doors. Combikey door opening push buttons have already proven their quality in buses, trams, subways, as well as in regional and high-speed trains.