The Quad Rears are 80/20 so that means you can use the rear quad for side fins on a 2+1 Setup.
Harley does this all the time.
- World Longboard Champion Harley Ingleby's Athlete Fin.
- Harley's XL template delivers maximum speed and drives for powerful surfers.
- Ideal for performance longboards, and surf SUP.
- Designed to be used with the FCS II Fin System.