Voda Full Foot Fins from Phantom Aquatics are made with 3 materials in the blade of Thermoplastic Rubber. This unique formula has Optimized Geometries to obtain the Best Effort/Performance Ratio. This Non-Vented Blade Fin has a Soft and Comfortable Foot Pocket for hours of Snorkeling Fun. The Open-Toe Design allows a larger range of foot sizes. The Blade of the Fin has Side Rails and a Ribbed Design to Focus the Flow of Water directly behind the Snorkeler for Optimum Power and Thrust.