This shows the 7.4m Sonic on a 288 board sailed by San Francisco's Kenny Hartz. Notice the perfectly opened leech. This is down hauled between the "Medium" and "Maximum" setting according to the guide printed between the second and third batten.

Above Kenny pointing upwind. Here you can see the dramatic amount of luff curve in the sail (mast bend). This is the secret to the Sonic's speed and stability when compared to other sails in this class.