The letter that Ray Johnson sent to Jiro Yoshihara was a mail art piece, and the members of Gutai realized that a new venue for presenting their work existed in the act of sending mail, which led to an active exchange of letters, or New Year's cards, among Gutai members. The New Year's greeting cards were not for the usual New Year's greetings, but were more like a catch-all of ideas, with a variety of letters (artworks) being exchanged. The postcard-sized small paintings were later sold in concrete card boxes. Some of these works were also packaged in envelopes and sent as gifts to overseas parties. In an interview, Maekawa said, "I was very happy to receive these works. Anyway, I made a lot of small paintings and sent them overseas, because they don't get much attention in Japan. I was always thinking about how I could make something interesting, considering sizes and shapes that would not incur postage costs."