Buffalo Blizzard 4-Foot by 15-Foot Long Air Pillow | Blue 18-Gauge Vinyl Material | Inflate Under Winter Cover for Swimming Pools PROTECT YOUR SWIMMING POOL - Buffalo Blizzard air pillows relieve the stress and pressure from the walls of your pool caused by ice in the wintertime. Prevent pool walls from splitting due to ice expansion and damage by using an air pillow. DESIGNED TO DEFEND - These air pillows have been designed to withstand sub-zero temperatures and treated with antibacterial & antifungal additives, as well as UV inhibitors to prevent fading. PROPER AIR PILLOW USAGE - Simply inflate your Buffalo Blizzard Air Pillow and place it under your swimming pool cover during the winter season. Do not overfill this product with air, because that will increase the risk of the valve popping out. PRESERVE YOUR WINTER COVER - Using a Buffalo Blizzard air pillow will keep water, ice, and debris from collecting in the center of your pool on your winter cover. Air pillows allow for easier cleaning and an extended life of your winter cover. BUILT TO LAST - The 18-gauge water bag kits are manufactured from high-quality, heavy-duty vinyl. This rugged material is extremely effective when used on above ground pools.