Optimal training tool for improving leg technique and power, designed for professional and competitive swimmers aiming to improve their underwater phase Innovative silicone fins for swimming feature a sloping surface and hydrodynamic slits in the top that allow you to swim with a faster leg kick and better control Customized for left and right foot with open heel design for the best possible ankle flexibility, allowing faster upwards motion and a more powerful downward leg kick Equipped with a short blade for maximum forward thrust, side grooves for better control and special notches on the bottom ribs for faster kicks; PVC free Kick fins are made of long-life silicone for maximum comfort and reduced chances of blisters, perfect for intensive training; Refer to size chart for correct sizing