Plug-in system comprising a plug and a plug-in module , wherein the plug is designed to establish an electrical connection with the plug-in module , the plug having: a plug member in which a plurality of electrical contacts are accommodated and which has a plug base that is designed to receive a collar of the plug-in module ; and a plug lever which is designed to be moved from an initial position to a final position and in so doing to pull the plug in the direction of the plug-in module by means of a lever arm that engages into the plug-in module , wherein the plug lever can be fitted on the plug member in two orientations and, in both orientations, the lever arm and the plug-in module engage into one another in such a way that the plug can be pulled in the direction of the plug-in module , wherein a plug-in channel of the collar is formed symmetrically with respect to the orientations of the plug lever , wherein the plug-in channel has, along a plug-in direction into the plug-in channel , a first section that provides two symmetrical projections , a second section that provides two symmetrical cutouts , and a third section that provides two further symmetrical projections , characterized in that the lever arm has a shaft about which the plug lever can be moved in an opening in the plug member , wherein the shaft is directed in the direction of the plug member , wherein the collar of the plug-in module has a plug-in channel which is designed to receive the shaft , and in that the shaft has a lever tooth which is designed to engage around one of the projections of the first section , wherein the lever tooth pulls the plug into the plug-in module as the plug lever moves from the initial position to the final position. a plug member in which a plurality of electrical contacts are accommodated and which has a plug base that is designed to receive a collar of the plug-in module ; and a plug lever which is designed to be moved from an initial position to a final position and in so doing to pull the plug in the direction of the plug-in module by means of a lever arm that engages into the plug-in module , wherein the plug lever can be fitted on the plug member in two orientations and, in both orientations, the lever arm and the plug-in module engage into one another in such a way that the plug can be pulled in the direction of the plug-in module , wherein a plug-in channel of the collar is formed symmetrically with respect to the orientations of the plug lever , wherein the plug-in channel has, along a plug-in direction into the plug-in channel , a first section that provides two symmetrical projections , a second section that provides two symmetrical cutouts , and a third section that provides two further symmetrical projections , characterized in that the lever arm has a shaft about which the plug lever can be moved in an opening in the plug member , wherein the shaft is directed in the direction of the plug member , wherein the collar of the plug-in module has a plug-in channel which is designed to receive the shaft , and in that the shaft has a lever tooth which is designed to engage around one of the projections of the first section , wherein the lever tooth pulls the plug into the plug-in module as the plug lever moves from the initial position to the final position. <EOS>