Wedding Ring Swallow
He then asks for a hanger. He straightens the hanger out and starts jamming it down his throat. Everybody is shocked.
You can see this trick here:
So he has a ring concealed somewhere at his body, somewhere he can reach it fast. He probably grabs it while the others are looking for the hanger.
Now notice something. We never see how he begins to stick the hanger into his mouth. This tells us something important: a crucial part of the trick happens there. You’ve probably already guessed it – that’s when he puts the ring on the hanger. He sticks the hanger into his mouth with the ring already on it. Then he just has to push it deep into his throat (this part is real – remember, Blaine is crazy when it comes to things like this) and pull it out. It looks as if he used the hanger to pull the ring from out of his stomach!
"I thought of the same explanation you gave, but there's something missing. They straighten the hanger but do not untwist the hanger end under the hook. Trying to wind the ring through the wire twist would be difficult, and probably damage the ring. Maybe he has a few pre-made hangers on him, of different colors, which are designed to slip a ring on easily. He gets everyone looking at the ring while he swaps hangers.
Or, he's just really damn good at untwisting just enough for the ring to get it looped unscathed. But he's got several people looking at him from different angles. Simplest of all, he'd have an assistant do it for him, during a shooting break.
Zooming in on the hanger after it's been pulled out, http://i.dailymail.co.uk/i/pix/2016/11/16/06/3A6DD5B100000578-3940714-image-m-115_1479278002706.jpg, shows it very loosely twisted, unlike a real hanger."