Blue Wave NL1971 Gorilla Guard Above Ground Closed Cell Pool Wall Foam, 1/8" x 48" x 75' Designed for use with above ground pools; Closed cell 1/8-in thick high-density wall foam padding Protects pool liners against rips or punctures Cuts heat loss; Creates a smooth wall surface Reduces metal wall corrosion Easy-to-use - install on the pool wall prior to liner installation