The outlet opening (5) is arranged at an angle of 45 deg. in the base of the housing (1) and is connected to an outlet support (4). The outlet has an odour lock formed of a water retainer forming an overflow wall and engaging an immersed wall (9). The immersed wall is fixed rigidly to the housing and the over flow wall is formed as a hollow pipe arranged vertically and tightly in the outlet. The immersed wall has a through hole (11) in its upper region which is closable by a cover (12) and through which the hollow pipe can be assembled and disassembled. The pipe may engage the outlet by an extension with a sealing ring (20).
