Harpster Tarps Heavy Duty Black Poly Tarps by Tarps Direct are waterproof, tear and acid resistant. The fabric weighs 6 ounces per square foot and is 11-12 mil thick with a 14x14 weave count. Grommets are spaced approximately every 18 inches and in the reinforced corners, for plenty of tie down options. The black color blocks out 100 percent of the Sun’s rays making this tarp perfect for providing shade and keeping you and your stuff cooler. UV resistant makes this tarp perfect for outdoor and indoor use. Useful for covering cars, boats, and firewood. It has many applications including camping, hunting, fishing, beach trips, picnics, RV trips, and much more.