Bark RFD 7" Prone FinDeveloped by the legendary Bark family, the RFD is the most commonly used fin for stock prone racing. Tested and developed by the best in the sport, the RFD works in everything from downwind to flat water conditions. Template Category Prone Racing Construction Fiberglass Size Medium Prone For use with 10'6", 12' and 14' Bark Prone Paddle Boards SPECIFICATIONS Center Fin Area 27. 03 Height 6. 84 Base 5. 64 Foil 50 50