Full Foot Full foot, thses fins use the hightest quality tpr foot pocket to reduce strain on the user’s feet. Drag Reducing Fin Vent Drag reducing fin vent designed to maximize fatigue while kicking. Pre-arched Pre-arched fin design results in more thrust per kick underwater. Super Channel Technology Super channel technology. the soft, pre-arched TPR material built within the fin’s blade scoops water throughout the kick, producing maximum thrust.