Tusa X-Pert Zoom Full Foot Fins	Innovative hydrofoil design and hybrid blade produce greater forward motion (lift) both on the surface and under the water. Propeller-fin technology and super lightweight design achieve the ultimate performance with less effort. Open-toe full foot pocket provides superb comfort and support. The FF-9 provides more speed and power with less effort and fatigue than traditional paddle blade full-foot fins. The FF-9 is a super thin, lightweight design, yet it generates maximum performance and comfort with minimum strain on the leg muscles when using a small bent-knee kick with a light rhythm. The Propelling Power Traditional fins only use repulsive force to create propulsion. This normally means that in order to create strong propulsion, maximum effort is required, resulting in muscle fatigue not only for beginners, women, and middle-aged divers, but professionals as well. The body moves left and right in reaction to the kicking needed to move forward, thus reducing propulsion. The FF-9 has a blade that is split down the middle, so it takes the shape shown in the diagram when kicked under water. This special blade shape creates propulsion (lift) by generating a pressure differential above and below the blade, in addition to the repulsive force created by kicking. The FF-9 is a fin that allows all divers to create propulsion using only a small bent-knee kick, with a light rhythm. A light kick reduces water resistance and creates less turbulence. Traditional fins required fin-work with large strokes in order to create propulsion, since they depended solely on repulsive force. The FF-9 obtains propulsion not only from repulsive force but also from lift, so it works ideally with a light, rhythmic kick. In other words, a small "bent-knee kick" will bring out this fin's best performance. This makes possible a light kick which creates less burden on the legs than with traditional fins. A light kick with small strokes reduces the diver's fatigue and the amount of air consumed.  Also, small strokes reduce the resistance of the water on the entire body moving forward and can create less turbulence, so propulsion is smoother. QTY: Zoom fin sizes X Small Small Medium Medium Large Large X Large Zoom Fins Cobalt Pink