Blue Waves 8-Year Solid Above-Ground Winter Cover is made from durable polyethylene with a 7x7 scrim count. This cover is designed to protect your pool from winter elements and prevent water from passing through. Heat-sealed seams are reinforced for added strength and the cover s black underside helps ensure a clean pool in the spring. It featured a generous 4-foot overlap for a proper fit. Included with each cover is a metal winch and a heavy-duty vinyl-coated cable for securing the cover through the metal grommets spaced every 2 feet. Backed by an 8-year warranty with the first year fully covered.