My twin fins utilize a single wing swallow tail. The two stood up fins on top of the pannel vee bottomed board make for a quick snappy ride. Twin fins are the definition of fun in small facey surf and have a place in everyones quiver. Generally ridden a couple inches shorter than your everyday thruster. They do effortless off the tops over and over again as you learn to surf off of your rail. I offer these boards both with flat vee bottoms and 4 channels. Four channel twin fins come as glass-ons only.