Adjustable Train Engineer Hats - Train Engineer Costume Hats (6 Pack) These hats are child size hats, they measure 5 inches high x 7 1/2 inches wide. Children can play dress up with these striped train engineer hats. These hats are also the perfect party hats for a train birthday party. These cotton train engineer hats are fun for kids to wear. These hats have an adjustable plastic band.