The patented Accel Electronics Secondary Trigger connects to the output of your factory coil and provides a traditional points-style output that triggers an aftermarket ignition box. Since the factory coil remains in the system, the factory ECU doesn't know you are running an aftermarket ignition system. This eliminates check engine lights and ensures proper performance on OBDII equipped vehicles. Also includes a 12-volt ''Auto on'' output that turns on your aftermarket ignition box as soon as you crank the engine. This eliminates the need to locate a key wire for your aftermarket ignition box.