The FCS II Accelerator fin is an oversized, all-round fin for a diverse range of surfers. Designed for surfers who like to attack the wave and surf with energy and power on critical parts of the wave. Functional template with flat foil on the side fins delivering fast, controlled directional changes. 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.The fin has 4.39" base and 4.58" depth.