Surge Protector (Surge protection Device) is an indispensable electronic device of a lightning protection device, in the past often referred to as "lightning arrester" or "over-voltage protection device" English abbreviated as SPD. Is a kind of a variety of electronic devices, instrumentation, communications lines to provide security and protection electronic devices. Surge protector's role is to fleeing into power lines, signal transmission line transient over-voltage limiting device or system can withstand the voltage range, or stemming the flow of a strong inflow of lightning, the protection of the protected equipment or system is not the impact damage.

Has been widely used in industrial buildings, commercial buildings and civil construction of lightning protection, as well as government agencies, schools, transport, public security, banks, petrol stations, room, intelligent residential areas of lightning protection.