Oceanic Vortex V-8 Split Fins Blue/Black Large Patented Nature's Wing Propeller Fin Technology. Advanced composite materials for ideal flex and memory. Side rails add rigidity to the oversized blades for increased lift power and efficiency. Ergonomically designed foot pocket accommodates virtually all foot sizes and boot styles. Angled blade for preferred angle of attack. Easy on/off fin strap with thumb loop. Easy adjust quick-release buckles.