Monofin and top not included. You will need a monofin which inside the tail creating the fin shape and making it swimmable. They are closed on the bottom and the tail slides in from the top. It is best to put it on as your little girl is entering the pool.
If the monofin isn't correctly inserted into the tail it can poke through and make a hole in the tail. All mermaid tails are non returnable.