A supply pipe for connecting an instrument for dental or surgical use to a control and supply unit contains fluid conduits and electric lines and includes at a front end a universal coupling for connecting different types of the instrument in a removable manner to part or all of the conduits and lines. The universal coupling includes fluid connectors coupled to conduits and electric connectors coupled to lines, wherein each of the connectors occupies a place on a front face of the universal coupling. The supply pipe contains at least one additional electric line including an additional conductor which is not coupled to one of the electric connectors, but to one of the fluid connectors of the universal coupling, wherein the dual function connector is arranged to provide a choice between a fluid connection, an electric connection or both.
