Midwest Canvas 21' Clear Round Solar CoverThis Midwest Canvas 21' Clear Round Solar Cover is designed to retain heat, reduce water evaporation, and extend your swimming season with its innovative solar technology. Made from durable, UV resistant polyethylene, this clear solar cover allows sunlight to penetrate deeper into the pool, maximizing heat retention and energy efficiency. The round design fits perfectly on 21 foot pools, providing complete coverage to minimize heat loss overnight and