Pocket Monsters Stamp 151 (ポケットモンスタースタンプ１５１) are a series of gashapon stamps made by Banpresto starting around 1998 or 1999. Not to be confused with the rarer Character Stamps, they are non-self-inking stamps, and came with clear plastic covers for the bases. While stamps of the first 151 Pokémon aren't too difficult to find, the later Johto Pokémon series (known simply as Pocket Monsters Stamp) is exceedingly rare, only becoming known to collectors outside Japan late 2009.