Ultra 18′ Round Grey Solar Cover, 16 Mil

No More Chilly Pool Water with the 16 Mil Pool Solar Cover. The 18 ft round 16 mil ultra solar cover is the most economical and environmentally friendly way to warm up your swimming pool’s water. Thousands of tiny air pockets capture the sun’s energy and transfer that energy as heat to your pool, raising its temperature by as much as 18 degrees(F).