I have an unscratched Papa Hummel's Old-Fashioned Pet Biscuit card that I don't intend to use, therefore I'm putting it up for sale.
The card looks as you can see above. The actual card will not be sent, only the code. I have only one code (it hasn't been used before).
More information about the item you can get in-game: Papa Hummel's Old-Fashioned Pet Biscuit - Item - World of Warcraft or Papa Hummel's Old-Fashioned Pet Biscuit - WoWWiki - Your guide to the World of Warcraft.