Let me start off by saying that this is a very comfortable and warm slipper. 5 stars in that regard. The only problem that I had with them is that they are a little on the small side for 12's. I normally wear an 11-11.5 and these fit, but only just.

You may want to order a size up.

UPDATE: I was way off on this. After breaking them in, I'm now swimming in them. I have to wear socks for them to stay on my feet.