Exemplary embodiments are directed to a metal-encapsulated, polyphase busbar switch disconnector and earthing switch, including a housing which, on each of opposite sides has three flanges that lie on a plane. Each flange being connected to one busbar and, on a third side, a flange is connected to a circuit breaker. The circuit breaker having conductor elements arranged in an interior of the housing. First conductor elements are connected to the busbars, and second conductor elements are connected to circuit breaker poles. The second conductor elements are aligned at right angles to the first conductor elements, which connect the busbars to one another, such that the first conductor elements are substantially U-shaped and are passed around the second conductor elements. A switch disconnector and earthing switch contact arrangement is provided between an inner housing wall and the first and second conductor elements.