The Pokemon TCG 151 UPC Promo Set features three new cards - Mew 053, Mewtwo 052, and Metal Mew 205, all sealed in a pack. These cards are part of the Pokemon 25th Anniversary set, with a Psychic attribute and a standard card size. Manufactured in 2021 by Pokemon, the cards are in English and feature a holo finish in the EX specialty. The promo cards are highly sought after by collectors and fans of the Pokemon franchise, making them a valuable addition to any collection.