30x40 Heavy Duty Silver/Black Poly Tarp - 10.5 mil - 14x14 Weave - 100% Waterproof BP1; 14x14 Weave Count - 10.5mil BP2; 24" Rust-Proof Grommets - Reinforced Plastic Corners BP3; Special U.V. Coating for Extended Outdoor use! BP4; Last 3-4 Times longer than regular tarps. BP5; 70% Thicker Polyethylene Coating