Four characters - Kan Ei Tsu Ho / Blank. 24mm, 2.19 grams. Komemura, Honsho, Edo,  Musashi Province, cast 1737-1742. Hartill 4.159.

Most Japanese coins are very rare. These coins are, however, common - they were inspired by the Ming dynasty cash from China. "Kan Ei Tsu Ho" means "Universal Treasure of Kan Ei".