Roughneck 6-Oz. Extreme-Duty Black/Silver Poly Tarp - 12ft. x 20ft. Provides superior durability and the best sun shielding capability Silver side reflects sunlight Black side prevents light penetration First layer is tightly woven 14 strands per inch x 14 strands per inch of polyethylene fiber Woven fabric has a double laminated coating of polyethylene, producing a durable weight of 6-oz. per sq. yd.