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. 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!