Wall Fitting, O-Ring, Nut, and Reducer for the Waterfall Return Assembly on 2006+ J-400 Series JACUZZI® Spas. NOTE: Figure 1, 2, 3, and 4 Only. Includes Wall Fitting(6540-167), O-Ring(6540-511), Nut(6540-791), and Reducer(6540-230). (Click the diagram on the left for a larger, actual image)