Crank Trigger Wheel Kit Flying Magnet Hall-Effect Bbc 8 In. Big Block Chevy Crank Trigger Kit 8 In. Wheel/Hall-Effect Sensor/Adjustable Timing Pointer Red MSD IgnitionThe MSD Flying Magnet Crank trigger is now available with a Hall Effect sensor making it the most accurate way to trigger your EFI. The kit installs easily and uses rigid aluminum mounting bracketry and hardware that will not flex and cause timing fluctuations. Powerful magnets are embedded in a 3 8 Inch thick aluminum trigger wheel that will send your EFI a clean signal for every firing. Most accurate way to trigger your electronic fuel injection