Check the listing for details. MSD 62023 Ultra 6A Ignition Control. Condition: New, Made in United States. Listed at 334.95 USD. Black - Compact design - full MSD power; The Ultra 6A Series continues to use a high speed controller that can make extremely quick compensations to the output voltage, multiple spark series, timing and rpm limits while maintaining precise timing and accurate rev limiting. The circuits and controller of the MSD have been thoroughly filtered to create protection against Electro Magnetic Interference (EMI). This version is 60% smaller and 50% lighter than the MSD Digital 6A (688 grams vs 344 grams). The Ultra 6A Series feature a capacitive discharge ignition design. The majority of stock ignition systems are inductive ignitions. In an inductive ignition, the coil must store and step up the voltage to maximum strength in between each firing.