This is a colorful Teenage Mutant Ninja Turtle themed first birthday cake smashing outfit! The diaper cover is in the colorful TMNT fabric! The hat is a one-size-fits-all hat, with the same fabric, and is modeled after a standard party hat, with elastic chinstrap. The optional party hat is covered with fabric to match the rest of the party outfit, has a green felt background with red, blue, purple or orange smaller felt one on top! Then it has colored trimming and pom pom to match the color you choose! The onesie is a Gerber brand so check the sizes! It has colored ribbon running down the sides, with matching colored "1". There is also a bow tie sewn to the onesie with the color matching of your choice. The colors to choose from are for the characters listed below: Blue: Leonardo Red: Raphael Purple: Donatello Orange: Michaelangelo The measurement sizes for this diaper cover set 12-18 months are: Leg is 9 1/2" and can stretch to 11 1/2". The waist is 16" and can stretch to 19". If you have any other questions about measurements, please don't hesitate to ask. Please check Gerber onesie sizes in picture posted.