The place in Canada that sells the WM planes told me that the S version was the only one available so thats what he sent me. It has the cowl around the engine but its a waste of time. Its short, and has a small diameter. This means that the cowl was tight up against the carb opening when held in position. By the time I dremelled just enough to clear the carb opening, about 2/3 of the top of the cowl was gone!!! I liked the original simple open plan but I ended up having to goof around with a cowl anyway. The plane flys great though! One tip, the landing gear wires in the wing has too short of an axle. If you can, replace the landing gear wires before gluing into the wing. The wheels as supplied were way too small for my grass field and I had to buy the axles that are attached to the original wires to accomodate the larger wheels. The plane is worth it hough. Have fun, Fast!