These wonderful practice tunnels are made of a sturdy material similar to canvas, yet weighs less than 15 lbs. They resist dogs nails and can get wet and dry without harm to the tunnel. (storing it when not in use is recommended for even longer life however). It is 15' Long with a 24" diameter opening. You can use it straight or curved. It condenses up for portability, and the spring coil is sewn internally so the dog can't catch on anything when running through it.