Introducing the Mermaid dress-up costume by Baa Baa Black Sheep. The outfit is made of lightweight satin fabric and allows for free movement. The colors are bright rich green and lilac. The waistband is stretchy for comfort and the top half is halter neck by a satin ribbon with an open back, just like a mermaid. The key feature of this dress is the gorgeous padded mermaid tale that follows behind.