Spotted by Boing Boing, I have nothing much to add to this description...

Although som may disagree, the kids Toilet costume is a very funny kids Halloween costume. Additionally, a Child toilet costume is perfect for every potty mouth kid— Use as a modern day Dunce cap!! One size fits most kids size 7-12.

... except, perhaps, "Best worn by a child named John.'"

Child Costume: Toilet [Anytime Costumes]