Now here's something unusual!
This is a "mint on card" phone card! All the cards here were likely sold in a similar packaging style. (similar to a gift card you see in stores) The card is either glued or shrink-wrapped onto a larger thick cardstock paper, to increse size/reduce theft. It is then able to be hung on a shelf/rack and then activated by a cashier in the store to give the initial minutes. Sometimes the card part would have extra info, like numbers to call for help/instructions/etc written out bigger.
This card is clearly an SA1 offering, with just the white parts of Sonic's face on an all black background. Photo & owned by Vercetti2021