Unused Only tried on a board once, these are unused spares. Please note that there are screw marks, and minor scratches from the beginning, and a slight burr from the molding process if you touch it. Product Details Set Contents: High-quality twin keel fin set (2 fins). Ideal for surfboards, shortboards, funboards, and longboards. Includes: Fin set, key, comb, screws Material Construction: Durable design combining nylon, fiberglass, and carbon composite materials Performance Features: Designed for a balance of strength and flexibility, enabling explosive speed during turns Compatibility: Versatile design compatible with three types of fin boxes, allowing installation on various surfboards Type...Fins Fin System/Fin Box...FCS Number of Fins...Twin Fins