The rat rods of surfing fins. In the mid 70's these fins were powering radical surf with high performance single fin surfboards. All the good ingredients for your single fin surfboard of choice: Retro's, Longboards, or 2+1 create endless possibilities with enduring design, upright foil, minimal flex. If youre riding 6.5/7.5 fins we recommend 3.7" sidebites. For 8-10 these are the ones you want to use for your single fin machine.