For a long time, racers have known that one of the best things to do to an engine to improve its performance is to stabilize the ignition timing. The MSD Flying Magnet Crank Trigger systems do exactly that by using four magnets embedded in an aluminum wheel. Although similar in appearance to other crank triggers, the MSD Flying Magnet design works on a different principle. Most crank triggers have a wheel, with steel studs sticking out, bolted to the harmonic balancer. As the crankshaft turns, the studs pass by a stationary magnetic pick-up, triggering the ignition. This pick-up can be triggered by other bolts, debris or even vibrations which will cause a loss of power or engine damage. The MSD Flying Magnet Crank Trigger uses four magnets secured in the aluminum trigger wheel that pass by a stationary non-magnetic pick-up to trigger the ignition. This "flying magnet" design produces accurate trigger signals and the non-magnetic pick-up cannot be false triggered, making this one of the best on the market!!