For Slide-in Fin Systems on all STX Sup and Hybrid boards. | | QUALITY Materials: The Nylon construction gives this stiffness yet enough flexibility. | | | M backfin for all SUP and hybrid SUP/WS size 9 | L centerfin for hybrid SUP/WS boards: size 12 | | Type: Fin | Size: L | Colour: Black | Original Colour by