These square pots are glazed only on the outside; the inside and bottom are left unglazed for breathability. The bottom has a drainage hole and four legs to ensure the maximum drainage.
They are Banko ware and made in Yokkaichi. Banko ware is known for donabe (earthenware pot), kyusu (Japanese teapot), and various types of bonsai pots.
Who Makes It
Morisun is based in Banko and specializes in distributing Banko ware bonsai pots.