These Quad Rears have a 50/50 foil so they are suited to quad sets which have the rear boxes set close to the stringer of the board.Neo Glass.These fins are designed to work with the FCS II carver side fins from the thruster set they are supplied as two fins to go in the rear fin plugs of a quad set-up.OVERVIEWElongated fin for performing long arc turns.High degree of sweep angle provides exceptional control off the bottom and when carving on the open face.Designed for power surfers who like to push hard against their fins and draw out their turns.IDEAL CONDITIONSOpen face down-the-line waves particularly good in point and reef breaks.BOARD TYPESRecommended for boards with deep concaves and moderate-to-extreme rocker.*Please Note: this fin is designed to be used exclusively with the FCS II Fin System and will not fit in the traditional FCS Dual Plug System. How Many fins?This :: Unisex > Surf Accessories Size: Small.