The cards do not have any special printing, and he shows you how to use your own cards with different back/face designs.
There are gaffs involved though. I would not hand the cards out for examination though, there are a few things that may be noticed. I am sure that there are magicians out there that would feel just fine about handing the cards out for examination.
That said, each of the cards can be displayed very freely and openly. For most of my audiences, this casual attitude would stop them from thinking that the cards are strange in any way.