Companies selling the device state it is designed to test components for protection from power surges and electrostatic discharge.
When they are fully charged, the device discharges them through step-up circuitry, which delivers a high voltage back into the USB port.
This device has been compared to the Etherkiller,[6] part of a family of cables that feed mains electricity into low-voltage sockets such as RJ45.
Earlier generations, including USB Killer v2, were developed by a Russian computer researcher with the alias Dark Purple.
A more recent version uses the piezo inverter transformer from a CCFL driver with a simple two-transistor resonant Royer oscillator, one-shot timer and a spark gap as a lightweight way to generate an 1800 V sharp pulse more closely simulating a low-power electrostatic discharge for mitigation and circuit testing purposes.