Dorsal Surfboard Fins Hexcore Thruster Set (3) Honeycomb FCS Base Red This FCS Brand Surfboard Fin Box Compatible Red Hexcore Thruster Set allows for a moderate amount of flex that while having a lighter material the flex pattern still allows you to have smooth rail - rail transitions through turns the inside foil technology provides freedom in performance.Another favorite of the pros and beginners alike this fin will suit the any surfer or those who want to push themselves to the limit. For surfers in the 100 to 195 pound range.Base: 4.41 / 112mmDepth: 4.74" / 120mmArea: 15.26" / 9847mm Sweep: 32.9 Foil: 80/20