The Camco RhinoFlex Elbow with Swivel Bayonet Fitting with 4-in-1 Adapter makes it easier to connect to dump stations. This bayonet fitting fits securely into four sizes of dump station inlets: 4-inch NPTs, 3-1/2-inch NPTs, 3-inch NPTs, and 3-inch slip fittings. This elbow fitting is clear, so you can see when your sewer hose is completely done draining. This 4-in-1 adapter has a built-in gasket for an odor-tight connection. This hose fitting makes the elbow compatible with any lug fitting, and allows it to rotate 360 degrees.