FCS II Harley Ingleby Longboard Fin - 5.5"/BlackHarley Ingleby's small single fin adds more tail release to longer boards. PC Construction. Overview World Longboard Champion Harley Ingleby's Athlete Fin. Small single fin adds more tail release to longer boards. Ideal for performance longboards, surf SUP's, and 2+1 set ups. Designed to be used with the FCS II Fin System. Ideal Conditions A wide range of conditions from beach breaks to point breaks.