Sky-boot like: The design of the new Cetma S-Wing footpockets include several high stiffness bands which are studied to hold the foot completely firm and constrained. This feature enable to better transfer the foot driving force reducing almost to zero dissipation due to rubber deformations. High stiffness sole: The blade pouch stiffness allows the blade to be perfectly constrained and to increase by 30% the efficiency of the any blade. Open flow system: this is designed to canalize the water flow creating a channel beside the foot, this "without spars" system has been studied to optimize the hydrodynamic efficiency. Anti-twist System: the front structure of S-Wing footpocket is designed with a higher stiffness U-shape reinforcement to stabilize the blade thus avoiding rotations in longitudinal axis. Comfort: designed to maximize comfort by wrapping and following the foot shape of the foot anatomically, this thanks to 7 size available from 35 to 48. Material used for s-WiNG footpocket is a rubber blend combining the high elasticity of natural rubber with durability of thermoplastic. Please refer to the size chart.