Bought the 13ft by 10ft, this is not a rigid material, aluminum is easily bent. Not very stable due to its size. 2 people assembly (a must).  Packaged anchor screws are no good, I recommend anchoring with custom screws from hardware store. Aluminum post are hollow I recommend using wooden post under it. Other the other hand, provides good shade, fabric is nice. Low price!. Overall, buy again? No, but maybe the smaller version from this brand, which provides more stability at a good price.