You will need a standard RV 4 inch sewer hose in the correct length to go from your RVs dump port to the parks sewer connecrion. You will need some way to securely connect, usually an elbow with various thread sizes that screws into the sewer inlet. You will need a bayonet fitting to connect the hose to your dump outlet. Connect things together and your good to go. Leave the black tank valve closed until time to dump, usually at least 3/4 full. You can leave the gray tank valves open. I generally close my gray valves the day before I plan to dump my black tank. I use the stored gray water to flush the hose and lines after dumping the black tank.
