Naked Viking Surf Medium JL Thruster Surfboard Fins (Set of 3) FCS & Futures SIZE: Medium - Large; WEIGHT RANGE: 145 -195 lbs / 65-88 kg / BASE: 4.35 inch / 11.0 cm; HEIGHT: 4.56 inch / 11.6 cm; AREA: 15.12 sq inch / 97.5 sq cm; SWEEP: 34.1 degrees FOILING: Flat SeriesIII - The exclusive NVS SeriesIII Foiling is designed to increase laminar flow (Hold), and decrease turbulent flow (Drag). The SeriesIII Foils work on a wider range or angle of attack which means you'll hold more speed through turns. SeriesIII Foiling designed on fluid dynamics research from NASA. The NVS SeriesIII Foiling is the most advanced surfboard foil on the market. FCS and Futures Compatible Fins Designed and Developed in San Diego, CA The NVS SeriesIII Foiling is the most advanced surfboard foil on the market