Like many others I bought a rafter (approx £50) for my Thule 4.5 metre awning. On breezy days it helped keep the awning tight and on wet days gave a slope either side to aid run-off. Whilst in France in June we suffered a huge downpour which flooded the campsite to a depth of around 5 inches within two hours. We were away from the van. When we got back it was heartbreaking. Despite having tilted the awning (always as a precaution) water (according to neighbouring campers) had gathered at one end, the higher end, its weight had pulled the strong guy rope pin out of the sodden ground and the leg had collapsed backwards. The rafter was bent in two! Fortunately the awning was not damaged but the rafter is a gonner. I am inclined to think that when it rains so fast that a weight of water forms on either side of the awning that the cause is the presence of the rafter, whereas without it water would have gone from one end to the other and run off without hindrance. I shan't be buying another rafter!