COVERfree is revolutionary liquid swimming pool cover technology. It is an advanced mono-layer product that helps save water and money by decreasing evaporation. It significantly reduces water evaporation and heat loss. COVERfree creates and invisible barrier on the surface of the water that works even when swimmers are in the pool. Save water, save heat and save money with COVERfree! Natural Chemistry Coverfree benifits your pool by: - Creates an invisible liquid barrier that conserves water and heat. - Reduces Pool Water Evaporation. - Reduces heat loss.