True Ames Hobie Fish Single Tab Twin Fin SetThe early 70s era design is True Ames' most popular keel fin set, and has become an industry standard for pairing with fish surfboards though it also works great with alternative wider tailed surf craft, too. The True Ames Hobie Fish Fiberglass Single Tab Twin Fin Set was designed alongside the folks at Hobie Surfboards. This set is a true classic that pays homage to the early days of San Diego style twin fins. Fin Size Detail Height Base Area Foil 5.