Super Soaker Nerf Hydro Pack by SuperSoaker. $19.99. From the Manufacturer Defeat the heat with the Super Soaker Hydro Pack. Drench the competition and then drench them again with this huge water pack's 100-Ounces of water. Adjust the straps for a comfortable fit and use it with any Clip System Super Soaker blaster (sold separately). When you sling the Hydro Pack on your back, you'll be ready to out-soak everybody.