RV SEWER KIT 15′ Rhino FLEX sewer hose and pre-attached specially engineered fittings to make it even more convenient for you. At the RV end of the hose, there is a super-tough bayonet fitting with 4 prongs for a more secure fit. At the dump-station end, we’ve added an easily detachable 4-in-1 adapter for fitting to 3″ slip or 3″, 3-1/2″ and 4″ threaded pipe. It’s a ready-to-use kit made with the toughest hose you can buy. With pre-attached fittings.