Water tubes are for use with inground winter covers, but are also great for abovegroud pool owners who have a partial or full deck around their pool. Help keep your cover securely in place by laying the water tubes on top of your winter cover around the perimeter of your pool. We specifically buy dual chamber water tubes because they won’t roll over like single chamber tubes can. Plus, if one side becomes punctured, there is still enough weight in the other tube to hold the cover down so you don’t need to rush to replace the tube right away. *The Great Escape recommends only filling the water tubes 3/4 full to allow for ice expansion when the water eventually freezes.