Future Fins Glass Fin Thruster Fin LARGE Size Also great for larger surfers or funboards! Genuine fins carved from multiple layers of fiberglass. The flex and durability are different from molded fins. Type: Fins Fin System/Fin Box: FUTURES Number of Fins: Thruster Fin Mid-length Fin Funboard Fin Shortboard Fin Fiberglass Fin L Size Thruster Fin Thruster Fin