Glass Flex Glass Flex (GF) fins are molded from engineering grade polymer. The flex of these fins has been designed to help novice surfers maintain speed and acceleration as they learn to execute turns and maneuvers. The FCS II Tool-Less System No need for a plate and screw. Ability to adjust your fin position in the box mid surf. Easily insert or remove your fin in seconds. No fin key required. Designed to be used in most existing boxes.
