A bath tap fitting in the known way comprises a securing device which can be attached to a mounting plate. This has a securing body which extends upward and in its upper area possesses a multi-faced outer contour. An outlet spout can be fitted to the securing body with a multi-faced seating aperture so that it does not turn. A locking screw can be screwed through a threaded hole of the outlet spout against the securing body so that two faces of the seating aperture of the outlet spout, enclosing an angle with each other are pressed against two faces of the securing body enclosing a corresponding angle. In this way the securing body is nullwedgednull in the seating aperture of the outlet spout. The outlet spout sits absolutely firmly on the securing body.