Blue Waves 12-year Solid Above-Ground Winter Cover is made from durable polyethylene with a 10x10 scrim count. This cover is designed to protect your pool from winter elements by preventing water from passing through. Heat-sealed seams are reinforced for added strength and the cover s black underside helps to ensure a clean pool in the spring. It features 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 a 12-year warranty with full coverage for the first 2 years.