Complete overhaul aftermarket electrical system.

Yes that's exactly what it is, an intertia switch. It just needs to be mounted vertically. I believe it's designed so that it will shut off in a front, rear, or side impact. I was concerned that it would trip during a hard launch, but after messing with it, I don't think that it will. You have to actually impact it to get it to trip. Moving it back and forth as fast as you can doesn't trip it but as soon as to slap it against something, it goes. I'm running a footbrake car so I shouldn't see any issues like one MIGHT see on a trans brake car.