With four easy-to-access external fill/drain valves and a 400 pound capacity, the Eight.3 Plug 'n Play Trapezoid 400 lbs Ballast Bag lets you quickly and conveniently create a much more optimal wake. Tuck it in the rear compartment, the side compartments, or the center of your boat (depending on the wake you're looking to create), fill 'er up and experience an elevated wake experience!