Bought this for my 9yr old daughter and I have to say, it is amazing!! My daughter wears a size 10 and I bought a size 10, it fits perfectly!! The fin is a very soft and durable. The material of the fin is like a scuba suit. The tail is also very good quality, stretchy and light weight yet durable. The ends of the tail have a thick plastic type rubber to prevent scraps and tears in the fabric. Definitely worth the money!