The Meiji promos are promotional cards that you can find in a Japanese box of candy. The candy is a cracker or cookie that is covered in chocolate, like a Whooper. They will start being sold on the 24th of February, with one promo card enclosed. There are a total of 12 cards in the set; Bulbasaur, Charmander, Charmeleon, Charizard, Squirtle, Psyduck, Pikachu, Raichu, Slowpoke, Cubone, Jigglypuff, and Meowth.
Thanks to the Official Japanese Pokemon TCG Website
for the scans and box images.