Operating in arc discharge mode to provide a conduction path for medium to high currents for short periods of time, TX4.5 high-energy triggered spark gap switch can withstand extreme temperatures and severe stress and harsh environments and requires only a low-energy, high-voltage triggering pulse. The trigger gap holds off a voltage across two of its three electrodes until a trigger pulse is applied to the remaining electrode, causing the switch to conduct. The triggered spark gaps are designed for use in explosives detonation, rocket engine ignition, missile stage separation, and other high-energy applications. The device is tested to MIL-STD-202D methods 204 and 107.