This is a set of 3 History of Sonic stickers. They came free with the Sonic Generations Soundtrack (there was a blue & a white version of this) but which version did you have to buy? Was it a pre order, or simply a special copy of the disk? The stickers seem big too. They're likely a Japan thing...but it was rumored that other countries got them. Write in if you know how or where these were available!