FOR USE IN BOARDS WITH OUR HI-PERF FIN BOXOffers a safer fin option to convert your Beater Original PRO (both 48" and 54") into a shore-break machine! Or convert your Stump or Skipper into a Twinny! Stiffer inner core with soft rubber edge. Includes two 3.5" safety-edge keel fins, fin key and C/S sticker. Designed in California, U.S.A. by Catch Surf.