These are special Sonic themed Christmas cards. Why are they so special? Because they have a DVD inside every one! So when you give this card, it brings its own gift too. The DVD you get is "Sonic Christmas Blast" , the single episode of the somewhat ill-fated mash up of SatAm Sonic & Adventures Of Sonic early USA TV shows. You can read more about the episode/special on the Shows Page of SonicGear. With how uncommon the special is today, it's interesting to see it inside of holiday cards.