"Installed in minutes. Nice that installation is not permanent, as later I might take ‘em off and shorten them up a tad and angle at 4 degrees (not really necessary). Also, whenever we need another roof these will stay. I put 4 screws on bottom row and 2 on top and they are solid. Great product. I can see where a clever person could cobble something like this together, but at your prices who would bother? "