The Robelle premium winter cover is the highest-grade cover for above ground pools. This cover includes a overlap, making this cover easier to secure to your pool than other pool covers. If you have a very large top rail, please consider a larger pool size. The cover should be able to comfortably float on the pool water without excessive stress. The tan top of this cover is coated to prevent UV damage & the bottom side is black to prevent algae growth. Includes a premium quality binding around the entire perimeter of the cover that prevents against wear & tear. The Robelle premium winter cover features the highest-grade scrim (threads per square inch) available. This cover is constructed with the highest-grade polyethylene material that weighs 5.2 oz./yard2 both the scrim count & material weight are good indicators of the strength of your pool cover. A cover with the tightest weave & heaviest material, like the Robelle premium winter cover will last longer than inferior covers. Two premium grommets are placed on center every four'. with these grommets, you should use the included winch & all-weather cable to secure your pool cover.