The chi machine I have is called the Sun Ancon. This link will give you more information:
It is sold by independent distributors. You will find several if you google it.
We chose to buy this model even though there are less expensive ones on the market. It was patented, but apparently the patent is expired so technically others can make the same machine. I read lots of reviews and a few thoughtful ones where the reviewer had tried others and said they didn't make them feel the way this one does.