The Superior pool cover is a premium solid winter cover. Solid pool covers do not allow water to pass through their material. This winter cover is intended to be used during the off-season. Please order by your pool size, as the overlap goes beyond the pool size listed. Please order a larger size cover if you have steps protruding from your pool. This cover includes a five-foot overlap. The Superior winter cover features a premium scrim count (threads per square inch). The Superior pool cover has a premium 12 x 14 scrim. Heavy-duty premium polyethylene weighs 4.5 oz./yd2. Both the scrim count and material weight are the best indicators of the overall strength and durability of your pool cover. Includes a premium quality binding around the perimeter of the cover that prevents against wear and tear and adds to the life expectancy of this cover. The sand topside of this cover is coated to prevent damage caused by the sun's ultra-violet rays and the bottom side is black to prevent algae growth. Premium water bag loops (water bags sold separately) are placed every four feet. Water bags or water tubes are the only recommended method of installation.The cover should be able to comfortably float on the pool water without excessive stress. Includes a 20 year warranty.