Put some extra ballast in your boat and get the most ride from more wake. The portable Launch Pads have large fill-plugs with screw-in caps for quick and easy filling. Simply place in the boat and pump water in to fill the heavy-duty bladder with UV-resistant vinyl cover. Single (Model 1175173) adds up to 540lb. Twins (Model 1175223) add 350lb each for a total of 700lb. extra ballast Fill kit includes 12V pump that can plug directly into a cigarette lighter style outlet, clear tubing for intake and outlet ports and ballast bag fill adapters