Reduce water evaporation with our 12-mil Rectangular Solar Blanket for In-Ground Pools. To optimize heat retention, this blanket has an opaque, blue color that allows the maximum amount of sunlight to reach the water. Thermal bubbles retain that warmth even after the sun is gone, keeping your pool water warm even on cloudy days and cool nights. This innovative technology can increase your pool’s temperature up to 15 degrees Fahrenheit. Backed by a 5-year warranty, our blankets are designed to withstand years of direct sunlight and harsh conditions.