Nagano Tetsushi I (Living National Treasure, 1900–1977) spent almost twenty years reviving the craft of chanoyu kettle-making using wazuku iron. At present, the technique has been passed down to Nagano Tetsushi II (1941–) and Nagano Arata (1973–), who continue to produce work by the mold casting and melting furnace method today at a studio in Okegawa city in Saitama Prefecture.