Details Captain Fin – CF Series – M – 5 fin These moderately raked, larger based, and evenly sized thruster and quad fins are a great-all-around addition for your modern quad or thruster shortboard. The center fin is a touch smaller adding a bit of release to your turns. The CF Series was designed for reliable performance in a variety of conditions and is a favorite amongst the Captain Fin team. If you can only have one five-fin set, this is the template to have.