4' x 4' Canvas Tarp 12oz/18oz Olive Drab with D-Rings Approximate finish size is 3'6" x 3'6" due to hems, seams. Weather may cause canvas to shrink. 100% single-filled duck canvas, industrial-rated. Treated with Canvak, the highest quality treatment available. Water-repellent, mildew-resistant. 12oz per square yard before treatment and 18oz per square yard after treatment. Sewn, fabric-reinforced zinc-plated steel D-rings every 3-4 feet along sides, brass grommets in corners.