It is difficult to categorise this effect.  Is it a puzzle or magic?  At best it can be termed a novelty.

This specially constructed card, when folded (or unfolded!), will turn itself inside-out, front to back (or vice-versa) and transform into another card.  The card itself is a puzzle – people are trying to figure out how it is possible to construct such a card.

Three different presentations are provided that attempt to put a magical element to this prop.
In “Transformer Card” (the title trick), a card is chosen from a deck, say, the King of Hearts (KH).  A prediction is shown to be the wrong card, say, Ten of Clubs (10C).  Magically, this card is folded (unfolded) and the 10C turns inside-out, and the back of the card is now showing.  Finally, it morphs into the correct card, KH.  Just as quickly, this KH becomes mismade, with its indices in the center inside of at its perimeter.  It then turns into a mismade 10C, finally, several folding of the card brings it back to the proper KH.
“It’s Always The ?” is a comedy presentation of the “Transformer Card”.  There is a slight difference in the presentation, and the climax is where the entire deck consists of the other card (10C in this case) which the spectator did not pick.
In “Inside-Out”, the chosen card is KH.  The prediction is shown as a wrong card, 10C.  It is then transformed into a proper KH.  However, when the spectator turns over his KH selection, she finds that it has now transformed into a mismade KH with its indices in the middle of the card!
You will be able to come out with different presentations, too!
The special card is well made and it flexes very smoothly.  The instruction DVD is also well produced.  In the DVD, Mark Mason performs and explains, and provides additional tips for the Transformer Card.
It is difficult to put a rating to this effect, too.  After considering its magical content and entertainment value, I give it a “4”.  If you like this type of effect, it will worth much more than the “4”.  If not, it will be much less than the rating of “4”.  (4/5 stars rating.)