Unfortunately, this article does not work as planned. I wanted one of these back in the days when they were advertised on the back cover of off-road magazines (next to the MSD ignition gauges). Eventually he decided to get one and he failed at every opportunity. Work. Disappointed as the concept seemed solid. I'm considering a hard switch now as I believe that while this device continues to monitor the amp change to turn the battery back on it just keeps draining the battery. It might work if I were the guy who would leave the headlights on and come back 12 hours later not knowing exactly how or when the device has any value.