It's useless
I give this 1 star for its concept. I cannot give it any further praises. The head band is too flimsy and does not grip the head sufficiently to keep the oxygen delivery tube in place. The least head movement causes the unit to move out of position. There also needs to be a clasp on the hose to fasten to a user's clothing. Unless the user has hold of the hose, it is impossible to move about without moving the entire unit. A total waste of money.
Rating: 1 stars