The lightning arrester insulators are a two-in-one product with a new composite structure, adopting a design philosophy of first blocking and then clearing, which enhances the insulating performance and anti-fouling level. They are suitable for insulating supports of overhead lines and also provide protection against lightning strike damage to overhead insulating conductors, porcelain insulator explosion, and reduction of lightning-induced tripping. The principle is: when the lightning overvoltage exceeds a certain value of the insulating blockage, a flashover discharge is caused between the arc rod and the steel foot of the lightning protection column, forming a short-circuit path. The subsequent AC arc then burns at the discharge gap to protect the conductor from burning. When used with insulated wires, this product also features a piercing power-on function, making installation and construction extremely convenient and reliable. It avoids core water ingress and corrosion without the need to strip the insulation layer, and also reduces the labor intensity for operators. By integrating the column insulator and the arc prevention hardware into one (at the same potential), it is unaffected by the supply side of the loop network (away from the power source), further simplifying and beautifying the line while reducing costs.