You will receive 1x Booster Box of Terastal Festival ex SV8a. Products will ship within 24 hours of purchase. If choosing the Live Opening option only Holos and higher cards will be sent. 
There are 237 cards in this set! The expansion features Pokeball & Master Ball Holo Patterns, and 50 SR+ rarity cards including some of the following: Umbreon ex, Roaring Moon ex, Gholdengo ex, and Pikachu ex!