This is the Mares Razor Pro Free Diving Long Blade Full Foot Fins for Spearfishing Features: Foot Pocket Incorporates Comfort and Efficiency One of the Lightest Free Diving Fins Side Ribs Support Blade, Channeling Water Flow Side Ribs (stringers) Prevent Lateral Slippage Design Consulted by Leading Italian Podologist Techno-Polymer Construction 5 Sizes of Foot Pocket to Choose Interchangeable Blades The innovative Razor fins deliver the best performance among all technopolymer fins currently on the market. They are a benchmark for the most demanding freedivers and spearfishermen.