I, thinking it was a good idea, decided not to use a thumbnail but rather the end of a blade to scratch off my card for microsoft xbox points. Well now I cannnot read the code and it appears I am "fubar" out of 20 bucks. There is anothef code on the card but that seems to be useless. Be VERY careful because looking into I hear even using your fingernail too hard can rake it off with the coating. I've never seem a card so fragile as this.
Just thought a head up might save someone this dilemma. Oh, and depending where you buy it they won't help either.