Zirconium matua, whakamahia mo te pupuha tundish.
Ko nga ahuatanga matua:
1. He pai te aukati waikura, kaore e kitea te whanuitanga o te diameter, te roa o te mahi ratonga, kaore he rerenga rereke, he ahuatanga marara;
2. He pai te mahi wiri wera, he pai te mahi anti-pahū;