This is a perfect product. We were looking for something to put on the top of our new pergola, which is 16 by 20. Thought of fiber glass sheets, but then that doesn't come off during the winter and snow will build up on it. I decided to try this product at 11 pounds, I was able to put it up and secure the corners by myself from the ground (on a ladder) without going up on the roof. after each wind storm, I go and tighten the buckets a bit more cuz the sail does stretch out. It blocks the sun perfectly, letting light in, but keeping the deck wonderfully comfortable in the mid afternoons, which was when we never could go out there due to the direct sun. We added some roll down shades and we've been able to enjoy morning coffee, afternoon lunch and evening cocktails in perfect comfort.