FCS II MF Performance Core Tri Fin Set Black FCS II Performer PC Thruster Tri fin set Acquista online FCS II Carver PC Tri fin set Acquista online FCS II Performer PC Thruster Tri fin set Acquista online. Sky opted to choose an existing template that matched her surfing style and will allow her to continue progressing and perfecting her turns. After testing a range of different fins, Sky landed on the versatile Accelerator Small template.