Gladon PP4550 45' x 48" x 0.50" Happy Bottom Pool Pad can add years of life to a pool and its liner. Made from a special high density closed cell polyethylene foam, HappyBottom Pool Pad cushions and protects the pool liner. HappyBottom reduces the potential for liner failure due to punctures. It also acts as a barrier to keep corrosion causing elements in the soil away from the metal components of your pool. HappyBottom acts as an insulator under the pool, reducing heat loss to the ground. Reduced heat loss can save energy and extend your swimming season.