I will be travelling to the tropics and wanted to make a rain poncho that was very lightweight and could be folded into a small volume. I did not want a completely waterproof fabric, both because of the weight and waterproof fabrics in high heat and humidity tend to become equally wet on the inside and the outside. I chose a high dernier fabric [lightweight ripstop nylon] to give me some water repellency in an occasional squall. I have not yet taken it to the jungle, but if I need to use the poncho there I will write another review to report how it performed. It certainly was easy to sew.