VINGLI 12Mil Solar Pool Cover, Rectangle Solar Blanket-Heavy Duty Solar Pool Cover for Above Ground Pool-Pool Solar Cover for Inground Pool (Blue, 16'x32' Rectangular)Brand: VINGLI Color: Blue Features: Extend Swimming Time The Solar Pool Cover is made of special material. The transparent blue cover absorbs heat through thousands ofbubbles during the day and releases heat into the pool, thus allowing for longer swimming time. Let you enjoy a pleasant swimming time! Notice: bubble side is down wheen use, normal the bubble will be a little deflated before sun exposure due to thprinciple of thermal expansion and