Keep your pool warm and your wallet unscathed by lowering your electricity bills this season with the Solar Sun Rings Swimming Pool Spa Heater Circular Solar Cover. Solar sun rings are much easier to set up and take down than regular pool covers and save you money in the process. The solar cover works by using sunlight to heat the pool throughout the day while the thermal blanket effect helps the water retain heat during the night.The cover also reduces the evaporation of water and chemicals, so your pool stays intact longer. The redesigned inner grid with added drainage grommets allows water to seep through the Solar Sun Rings without sinking. Dirty pool? Simply move the rings around while cleaning your pool instead of going through the hassle of removing them all. Enjoy your pool without worry with the Solar Sun Rings Swimming Pool Spa Heater Circular Solar Cover.