RSK / Twin flaps are preferably used at stormwater pumping stations. They allow the mutual opening or closing of two flow paths with one construction, replacing the slides / contactors required for conventional design. Rotatable flaps are generally easier and safer with regard to their movements. They can be loaded on the pressure and tension side. In case of flooding, RSK / Twin flap gates close the opening to the receiving water and at the same time release the flow path to the flood pumps.