A combination of at least two electromagnetic switching devices, each of which is provided with a plug-in connector socket and can be fixed side by side on a support in a stationary position in relation to one another and can be connected to form electrical contact by means of a connection unit. The connection unit includes an electrical conductor connection and a plug-in connector system. The conductor connection is encased by a housing of the connection unit and the plug-in connector system is encased by the lateral faces of the connection unit that face the switching devices. The plug-in connector system is configured to be displaced on the lateral face of the connection unit towards the lateral face of the neighbouring device in the connection unit housing.