11.5' Triangular Shady Outdoor Sail (Red) Effective against harmful UV blocking. Air circulation possible - Specially knitted high-density polyethylene fabric. It can block harmful sun rays yet remains totally unaffected by moisture and nature temperature extremes. Enviromental temperature below the shading sail can be lowered up to 6.5 degrees centigrade! Low maintenance - Just clean it with common detergent & water.