Our silver tarps are used to cover for Sun / Rain / Snow / Dust- All weather protection and are manufactured with a heavy UV polyethylene material to reflect the sun UV Rays . Grommets All Around the Tarp Waterproof Polyethylene 14 Mil Thick Mdew Resistant Material Resists Acid Resists Tearing Rope imbedded around the perimeter of the tarp Flexible in freezing temperatures A plastic collar bar is reinforced on all 4 corners of the tarp. The silver tarps are treated for UV protection