Wakeboard Boat Ballast Bag w/Cover, 550lb Wake Enhancement Fat Sac, Fill Water Sacks for the Ultimate Wake Enhancer Wakeboard Boat 550 lb Ballast Bag w/ Cover PORTABLE - Our wake enhancement kits allow you to take it out and fill when you need that crazy huge wake, and stow it away when you are done. HEAVY DUTY - This kit includes a heavy duty mildew resistant 30 Gauge PVC bladder and heavy duty cover to help avoid puncturing. NO VALVE LEAKAGE - The bladder has 2 drain and fill holes with valve flaps that open when the pump is inserted and close off when the pump is removed Our heavy duty cover has 2 easy access holes for the fill and drain valves, heavy duty zipper, and straps for repositioning when full