100% Natural RubberThis innovative rubber fin offers a whole new angle on trainingEngineered with a unique 10º blade angle to provide maximum stability and engagement throughout the kick cycleAllows you to dramatically increase your kick cadence without sacrificing techniqueAngled blade maximizes down kick segment, maximizing propulsionExtended foot pocket allows for ultimate comfortMidfoot flex points help eliminate crampingSculpted side rails engage hip rotation and downkick drive Speedo Unisex-Adult Swim Training Fin Switchblade