The Bestway 9'10" x 6'7" Pool Cover can be simply laid out over the top of your pool to ensure your pool's water stay free from debris and ready for your next swim. Providing insulation and acting as an effective barrier against leaves and insects, this pool cover has also been designed to leave a slight gap around the edges of the pool. This gap provides the necessary space for the water to breathe and keep it in optimum condition. The built in drain holes also prevent water accumulation. In addition, by covering the surface area of the pool it also helps to reduce water evaporation and therefore is a great way to cut on costly water bills.