Hi Edouard & Kevin I ordered the 18 X24 version years ago and I use it all the time. I had it rolled up in the tube until last season when I went ahead and mounted it on a piece of plywood that I found, much easier to use now that don't need to keep my hands on it so it does not roll back up. well worth the money, he did not have a GS diagram years ago, but he may have one now you would have to ask..