Mermaid Tail Fin - MonofinOur patented mermaid monofin (swim flipper) is the best monofin available (US Patents 9561401 and 9925416). Not only does it help you swim like a real mermaid, it keeps feet from sliding around, is so comfortable to wear, and won't break. Unlike other monofins, our swim fins do not require any babying. You can bounce on the tips, push off pool walls, even hop around in them without any fear of the fin breaking though you can break so please be careful.