Not sure, but they look the same.
Quick rant....I don't like how the Pari Proneb Ultra II doesn't have a good spot to put the neb when you're done. It has a place for it built in to the machine but it's very difficult to get the neb to stay put in the slot. I think the Pari Pro Neb Ultra had a great place to put the neb, it fit very well. However I do like that it's a little smaller then the first one. Pros and cons I suppose.