HPI Enviro Mesh Silver Coated Winter Cover with 3-Foot Overlap for 21-Foot Round Above-Ground Swimming Pools DEBRIS FREE FOR ME: Keep unwanted items from falling into your swimming pool while closing it up for the season with the use of the Enviro Mesh Winter Cover. Save time and energy on maintenance whenever you are ready to open up again as your pool will be free from debris. FULLY COVER YOUR POOL: The Enviro Mesh Winter Cover comes with 3 ft. of overlap allowing for a secure installation. This additional material is used to compensate for lower water levels, use of an air pillow and the swimming pools top rails. Secure this cover to your swimming pool with one woven tab placed every 4. Includes a vinyl coated cable and winch. DRAIN THE RAIN: Winter covers are designed to protect your swimming pool against rain, snow and high winds. Enviro Mesh is the strongest mesh material available with a reflective silver coating to speed up the melting process. This winter cover allows rain and melted snow to pass through the cover and into the pool, elongating the longevity of the material. DESIGNED TO DEFEND: Close your pool confidently with double stitched hems that are triple reinforced for strength and rugged mesh made from tough UV protected woven polyethylene. The scrim is tightly woven, allowing almost no sunlight to seep through your winter cover resulting in a virtually algae-free swimming pool in the spring. WINTER IS COMING: The installation of a winter cover will likely require some assistance from friends, family or a friendly neighbor. In advance of seeking help, the water level should be lowered beneath the skimmer, winter plug inserted and the water winterized with closing chemicals.