Professional winter pool cover for 18 x 36 ft. in-ground pools. This pool cover has a 5 foot overlap, which is the material included beyond the pool size, making this pool cover easier to install. Since 1973 Robelle has been offering the best pool covers for pool owners. This cover has more than twice as much overlap as other brands, making it the easiest pool cover to install. Including overlap, the cover size is: 23 x 41 feet. This Professional pool cover is constructed with professional polyethylene that weighs 3.7 ounces per square yard (125 grams per square meter). The material is woven with a 12 x 12 scrim. Scrim is the number of threads per square inch. Material weight and scrim are the best indicators of the overall durability and expected longevity of your pool cover. With over 50 years of experience, Robelle has designed this Professional winter pool cover with an exceptional focus on quality for this season and years to come. Constructed 85% heavier than industry standard. Backed by a 15-Year Warranty that is the best in the industry. We are real swimming pool experts that are here to help with all of your swimming pool needs. This is a solid winter pool cover that will not allow water to pass through. More pool owners have trusted Robelle for their pool closing needs than any other brand. Exceed your expectations when you choose a Robelle brand pool cover. This pool cover will protect your pool from winter elements throughout the offseason. Designed for superior protection against snow and ice. Cover should be able to float loosely on the water, consider going up a pool size if you have steps or a buddy seat. Using vinyl water weights around the perimeter of the pool cover is the only method of installation we recommend. We do not recommend having excess cover material on your deck. Fold excess materials under water weights. Where cover may be exposed to corners or decking please pad the cover with material from an old cover or another soft material. Includes loops for water weights. Water weights sold separately.