A Prismatic Surprise Box is a special Pokémon Trading Card Game (TCG) mystery box from the Scarlet & Violet—Prismatic Evolutions expansion, containing four booster packs, card dividers, a code card, and a guaranteed foil promo card featuring Eevee or one of its evolutions (like Umbreon, Espeon, Sylveon, etc.) with a special prismatic stamp, all housed in a useful storage box.  
What's Inside:
Dividers: Cardboard dividers featuring Eevee and its evolutions for organizing your cards. 
Code Card: A code card for the Pokémon TCG Online or Live. 
Storage Box: The box itself serves as a storage case for your cards. 
Eeveelution Promo: One foil promo card of Eevee or one of its evolutions (Vaporeon, Jolteon, Flareon, Espeon, Umbreon, Leafeon, Glaceon, Sylveon). 
Booster Packs: Four booster packs from the Scarlet & Violet—Prismatic Evolutions set. 
Why It's Popular:
Guaranteed Promo: Collectors love the guaranteed Eeveelution promo card with its unique stamp. 
Collectibility: Eevee and its evolutions are very popular, making this set desirable. 
Mystery Element: The surprise of which promo you'll get adds to the fun.