Plastic Adult Size Construction Helmets Hats (12 Per Package) 22 1/2" circumference inside of the hat 10 1/4" x 8 1/14" One size fits most Lightweight plastic Perfect for dress up or Halloween You can return this item for any reason and get a full refund: no shipping charges. The item must be returned in new and unused condition. Go to Your Orders to start the return Print the return shipping label Ship it!