The Surge Coil Blueprint is a blueprint that allows you to craft the 
Surge Coil, a deployable device that electrifies the area around it. When placed, it periodically sends out an electric pulse that briefly stuns both ARCs and other Raiders who come too close. This can be useful for controlling areas, buying extra time during combat or looting, and escaping fast-moving ARCs like 
Shredders.
You can find the Surge Coil Blueprint by looting various containers, such as lockers, desk drawers, cupboards, and industrial crates, during the Electromagnetic Storm map condition. You must be in a map where this condition is active. Check the Event Timers to see when the Electromagnetic Storm is running on any map. It has been reported to drop in areas like the Testing Annex, Water Treatment Facility, and Hydroponic Domes within the Dam Battlegrounds, among others.