Vipers' have a soft neoprene padding glued into the inside top of the fin. This not only pads the top of your foot, but also helps to prevent blisters. The blade of the fin is symmetric. They do NOT float, and offer both short and long blade styles. The Viper's strength does not come from being rigid and stiff. It comes from the blade's patented design which produces torque (an increasing resistance to flex) and "snap" to the blade (memory). These actions channel the water between the vertical side rails and off the straight blade tip for a directed thrust. This produces the most efficient kick possible.
This is a seven inch blade with full length side rails for maximum power and thrust. This model has the fastest prolonged speed and produces excellent wave stability. It uses a longer, more powerful kick. Has a yellow splash on the blade.