Sean Mattison is an American former professional surfer and current professional surf coach, most known for designing "The Nubster", a fifth surfboard fin. Mattison is also the designer of his own alternative high performance surfboards and surfboard fins named Von-Sol.In 2009, Mattison worked as Assistant Coach alongside Head Coach Ian Cairns to coach the USA Surf Team of the 2009 ISA World Championships. The team scored a gold medal, prior to which the USA had not won a Gold Medal since 1996.