You’re seeing the tail end of one of my original thrusters that opened my mind to the benefits of the design. Single to double concave through the fins with one tweak, the foil. I push more foam up front to allow for easier paddling and a solid platform for front-footed surfers such as myself. This design works well as a quad or 2+1 for all types of surfers out there. The rounded pin allows for some real nice cut backs and will smooth out your surfing while still providing a pivot point for all of those ripper shredders.