Naked Viking Surf Med/Large Bronn Quad Surfboard Fins (Set of 4) FCS & Futures SIZE: Medium/Large: Weight: 145 - 210 lbs /FRONT: BASE: 4.44 inch, HEIGHT: 4.45 inch; AREA: 14.76 sq inch; SWEEP: 29.7 Degrees / REAR BASE: 4.06 inch; HEIGHT: 3.91 inch; AREA: 12.4 sq inch / SWEEP: 32.5 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. 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