• Single wire operation  to preserve stock appearance and simplify wiring. • Active dwell control  to maintain high RPM spark energy while reducing coil heating at idle. • Auto shut-off  to prevent coil damage or dead battery if the ignition is accidentally left on. • Hall Effect rotary-vane sensor design compensates for worn bearings and distributor end play. Magnetic sensor is unaffected by oil, dirt or other contaminants, unlike optical systems. • Over-voltage protected against damage from high amp battery chargers, reversed battery or improper wiring.