FCS II Performer medium-sized 5-fin set, with a fin key, made of a slightly softer material. It's said to be compatible with any board. With FCS2, starting with the Performer and experimenting from there is the quickest way to go. - Model: FCS II Performer - Size: Medium - Type: Thruster, Quad - Included: Fin key Thank you for looking. Type: Fins Fin System/Fin Box: FCS2 Number of Fins: Five fins (5FIN)