Blue Wave 36-ft x 18-ft Polyethylene Solar Rectangle Pool Cover

36-ft x 18-ft Polyethylene Solar Rectangle Pool Cover. Designed for rectangular in-ground pools. Increases temperature up to 15 degrees. Retains heat to keep water ready for swimming. Prevents water evaporation and heat loss by 95%. Stops leaves and debris from landing in the pool. Intended to float with bubbles face down. Reusable from season to season. 6-year warranty