Another idea about cast iron aka gang duc: https://gangduchanviet.com - Han Viet company sell man hole cover and grating.

We can see the change in the design of the garden lighting today. From the use of cast iron columns, aluminum, people now prefer to use led poles. In Viet Nam, led pole is quite new.

Buy lamp post or cot den san vuon from TK Lighting chieusangxanh Brand - the most famous one in Ha Noi, Viet Nam.