Our Spa Solar Cover can warm your spa by up to 15 degrees Fahrenheit! This 7-foot by 7-foot blanket has a thickness of 12-mil and is loaded with thermal bubbles that retain heat at night and on cool, cloudy days. The transparent blue color of this cover allows the maximum amount of solar rays to reach your spa for optimal heating. This solar cover is UV protected so it will last under the most intense sunlight. Our square solar blanket is easily trimmed to fit any round spa as well. Harness the power of the sun to heat your spa with the Spa Solar Cover from ToySplash.