FCS II Mark Richards Twin + Stabiliser Surf Fins (M-L) - Cyber Lime/BlackFCS II Mark Richards Twin + Stabiliser Surf Fins MR's twin + stabiliser template. Exceptional pivot off the top, while center fin adds control. Performance Core (PC) fins are made using a multi layered resin transfer molding process. The flex pattern in PC fins extends progressively from the base through to the tip, helping the surfer to maintain drive and hold through a turn. This versatile fin material is light, and can be used in a variety of