LIGHTNING ARRESTER

https://www.hbygle.com/products/power-line-lightning-protection-arrester/

A lightning arrester for sale is a device employed to safeguard electrical equipment against lightning-induced overvoltage, restricting both the duration and amplitude of freewheeling. Typically, the advanced lightning arrester system is installed between the power grid conductor and the ground wire, and occasionally adjacent to electrical windings or between conductors.