At Fin Fun, safety is the top priority. The patented design of the monofin sets the standard for quality and comfort. Unlike other monofins that require you to strap your feet or ankles in, the Fin Fun monofin is designed to fit snugly on your foot while allowing for quick removal in or out of the water. The monofin can be slipped under the tip of mermaid tails or used separately. Made from high-quality neoprene for diving, the patented monofin fits perfectly and comfortably around the ankles for a pleasant swimming experience. The indestructible polypropylene insert gives the monofin its perfect shape while providing flexibility and mobility in the water while swimming. The Advanced version offers additional comfort and higher quality with reinforced ends and inner padding.