Before anything else, the "DUO D'ARC" is a beautiful kite : a rainbow in motion. Its flight is passably clean, fly it slowly or else, its sail will close up on you. Avoid the edges of its restricted wind window and also flying up backward. The lateral slides won't work as they do with several "4 liners" unlike the Revolution. In fact, flying is quite particular : mainly, the forward-rearward movements of the handles tend to re-stabilize it (as for an arch). When it spins upon itself, its double strip of sail tend to corkscrew flexibly with elegance into space and that is the way I dreamed of it. Finally, I must admit that th results I obtained owe much to the experiments made on the Sled by Sylvien VENET, to the explanations I got from Etienne VEYRES who created the arches, and also to a technical improvement made to the Sled by Georges RIVALS.