The Tarp Nation Heavy Duty 18oz Canvas tarp with D-Rings is made of industrial grade 100% cotton. – We sew in industrial strength, rustproof D-Rings every 3′ and reinforce them with extremely durable 4-layer canvas patches. -These patches will prevent the D-Rings from pulling out due to high winds or extreme strapping conditions, extending the life of your tarp. -Our panels are double chain stitched together with rot resistant thread. All hems are Rope Reinforced and double lock stitched for the very best durability. -We use Canvak on all of our canvas tarps for the best in water, mold and mildew resistance. This makes our tarps 18oz after treatment. -Canvas is breathable to let moisture out and keep your valuables dry. This Heavy Duty Canvas tarp can be used around the home, construction site, farm or wherever you need to keep valuables covered. With Old School construction and reliability, its hard to beat a Tarp Nation canvas tarp. All Tarp Nation canvas tarps are Proudly Made in the USA!