The couplet is: "Ri Li Xia, Gan Kun".

Some people also translated it as: bright crystal shines all over the world, bright crystal shines all over Gankun town.

This word comes from the strange couplets in seven old Temple of the Eighth Division, and there is no consistent answer at present. There are several interpretations of this couplet in the old temple, but most people think that the word "Hua" means "Hua". Now I can't type it with the input method.