Buffalo Blizzard Blue 8-Foot Long Single Chamber Water Bag | 12 Pack | 18-Gauge Vinyl Material | Secures Winter Cover to Rectangular Swimming Pools SECURE YOUR WINTER COVER - Keep your winter cover on your swimming pool during the cold and windy winter season with the use of water bags. All water tubes come with a leak-proof valve that is conveniently placed for ease of filling with a garden hose. Use these bags to weigh down your winter cover on your concrete or decking for an in-ground or above-ground swimming pool. DESIGNED TO DEFEND - These water bags have been designed to withstand sub-zero temperatures and treated with antibacterial & antifungal additives, as well as UV inhibitors to prevent fading. PROPER WATER-BAG USAGE - Fill water bags  -  full to allow room for water freezing expansion during the cold seasons. If you are having trouble closing the valves, try soaking them in warm water. EASY TO HANDLE - Close your swimming pool without any hassle with the help of these lightweight, easy to carry water tubes. Once you have your winter cover in place, slide these bags through your covers water bag loops before filling them with water. BUILT TO LAST - The single chamber, 18-gauge water bag kits are manufactured from quality, heavy-duty vinyl, keeping your pool cover secure all winter long.