Size:Large (10-12) Product Description This Cookie Monster Tween Costume was designed especially for your tween. The costume includes a red 100% polyester dress with character printed accent. It also comes complete with leg warmers and character headpiece. From the Manufacturer This Cookie Monster Tween Costume was disgned especially for your tween. The costume includes a red 100% polyester dress with character printed accent. It also comes complete with leg warmers and character headpiece.