We made adjustments on the PIRANHA to adapt the Multi-Fins use and we propagate that to the Single wave. In these adjustments there is the 2D profile, the "foil" used, the amplitude of the bumps and their frequencies. Basically for a Single fin use the PIRANHA is a bit more manoeuvrable and gets more lift at low speed against HB Concept which is faster with a little less drag. For upwind capability they are quite similar. Possibly the PIRANHA will replace HB Concept eventually (because not enough market for both) but one is not necessarily the version 2 of the other.