These are flashcards, or vocabulary cards, from "Tango-oh" (Word King). Honestly, it takes a lot of effort to cut these out, so I recommend that those who want to use them buy pre-cut ones. Both the flashcards 1 and 2 are out of print, and the list price for both together was over 4000 yen. I think everything is there, but I'm not certain, and there's some writing on them, so they're a bit cheaper. They're fine to use. I recommend them as vocabulary books because they're very easy to use.