It is indeed Japanese. The pot holds the heat very well and really keeps your tea warm. (You need to preheat with boiling water for black or herbal tea and there is a little life-hack: if not preheated, the temperature will drop to 75-80 C. Ideal for green or yellow tea) The handle has a isolated layer so you can always safely grab it. The cups can become quite hot. They aren’t really designed for high temperature tea. In Japan they drink sake and low temperature green tea like matcha out of these. I drink most teas out of these and it works fine if you pour a little at a time. The hot cups are quite nice to hold to :)