Awesome Mermaid Tail Fins for little mermaids , kids andamp; adults ! This monofin tails are designed as Mermaid Tails for swimming in the pool With the cool mermaid look, they also teach little swimmers an equal use of up and down kicks, builds leg strength and motivates them. For the sizing these Mermaid Fins has an adjustable strap which allows usage for a wide range of sizes. Please check out the link for more details