Heavy duty silver tarp fabric: 14x14 weave. 10 MIL.Built-in UV protection on both sides for superior sun light protection and longer life.Rust Resistant grommets approximately every 18 inches along all sides.Heat Sealed Seams. Rope Reinforced Hems. Plastic bar reinforced corners for added strength.Heavy duty silver tarps are waterproof, mildew resistant, rot resistant, tear and acid resistant.Size is cut size. Acutal tarp finished size is up to 3% or 6 inches smaller, whichever larger after hem and heat-sealing of seams.Heavy duty silver tarps widely used for roofing, woodpiles, trailer and RV covers, landscaping and outdoor storage.