Equalizer ring: a ring-shaped metal fitting that improves the voltage distribution of insulator strings. The function of the voltage equalization ring is to prevent side lightning strikes and is suitable for AC voltage forms. It can evenly distribute high voltage around the object, ensuring that there is no potential difference between the various parts of the ring, thus achieving the effect of voltage equalization. But in the "Code for Design of Lightning Protection of Buildings" GB50057-2010, the "equalizing ring" has been renamed as "equipotential bonding ring".