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Rainbow SPEEDWINGS -  the concept is simple and proven to work.  Another breakthrough from Rainbow Fins.  When the water flows past a fin, lift (energy) is created.  Because your fin is in a dimensional environment (water) it loses lift to "tip vortex".  Tip vortex is when the water curls around and off the tip of your fin.   This creates drag which slows you down.  The SPEEDWING solves or reduces this problem by redirecting the "tip vortex" away from the fin.  This means more speed which equals more maneuverability which in turns equals more FUN !
available in plastic or NOW PROCORE
size: 4.6" front fins with a 4.4" rear fin
Don't let the size scare you.  This set up is designed for every surfer that wants to get more out of their surfing.  You can also use the front winged fins for your quad set up.