Now you can dress up your future Justice League Member as the most powerful woman Superhero! This adorable Wonder Woman Onesie Halloween Costume is a fantastic Costume for your baby’s first Halloween. The Wonder Woman Onesie comes with the red onesie with wonder woman logo, attached blue tutu, star-studded pants, booties and headpiece. This costume is available in sizes Newborn (0-6) and Infant (6-12). Polyester. Cold Wash.