I've tried using those, and it feels awesome at first. Then when I try to take it off my head though, the crazy knots it created in my hair destroy any good feeling that was there previously.
I may get a downvote. But my cousin had this and caught everyone by surprise with it. Let's just say, i still flip my sh*t when someone does that to me.
Those are the most amazing things ever. It's a head messager, and you put it over your head and bring it up and down. Ugh, I still have one.