Made of heavy duty industrial Polyethylene. Material is laminated on both sides for maximum weatherproofing. Designed for maximum strength and durability. Lighter than canvas. Outer edges have been reinforced with rope Sealed in hem for extra strength. Grommets and Cross Weave - High Strength Rust-Resistant grommets on each corner and approx. 3 feet. Cross weave fabric for tear-resistance. Tarp sizes are 6" less in length and width for finish size.