Found this at a yard sale this weekend. It's made of metal and is just over 1 inch long. The "balloon" is made of thin glass.
Reminds me of a "flying machine" from an old science fiction movie.
It's probably a little prize that came out of one of those coin op machines, where all the prizes were stored in little capsules. You would insert a nickel, and one capsule would roll out and you would open it for the prize. It could also be an old cracker jack prize.