The Coolaroo Square Shade Sail features Coolaroo`s unique commercial-grade knitted fabric that`s specially designed to breathe and block at the same time. The unique construction of advanced polymer fabrics allows cool breezes to flow through and hot air to escape. This state-of-the-art material blocks up to 90 percent of the sun`s harmful rays yet is totally unaffected by moisture and natural temperature extremes. This fabric lasts longer and provides great protection from nature`s harshest ele ments and because it`s knitted and not woven it won`t tear or fray. Hang this shade sail over your patio or deck to stay cool and comfortable even on the hottest days. It`s available in 11 feet 10 inches or 17 feet 9 inches. There are several stylish colors to choose from as well. All the necessary hardware for installation is included