Seac Motus Long Free Diving Soft and Powerful Fins for Spearfishing Freediving Innovative closed-shoe free diving fins Interchangeable blade made from special techno polymer that maximizes flexibility and reactivity Hard thermoplastic rubber foot pocket with dual material density 22-degree angle between blade and foot optimizes thrust power with less effort Different sizes fit men and women over a wide range from men's US sizing 4.5 to 14