A plug for the connection of a high-voltage cable. The plug comprises a jacket configured to be inserted into a connection receptacle of a high-voltage electrical appliance in order to connect the cable to the appliance, wherein the jacket includes a recess created therein, and a sleeve positioned around the jacket to form an insulating interface between the jacket and the receptacle, with the sleeve being located in the recess of the jacket and configured to hold the sleeve on the jacket.