The “Flame-Thrower I” high-performance coil delivers 15% more spark, which allows for larger spark plug gap for added power, smoother response and better fuel economy. Delivers a full 40,000 volts. The “Flame-Thrower II” coils maximize energy and reliability over the full rpm range, enable larger plug gaps for greater fuel economy and increased power levels and they're 50-state legal. These coils are rated at 45,000 volts and are intended for use with the “Ignitor II” ignition system. The “Flame-Thrower III”, 45,000 volts, 50 state legal, oil filled, 0.32 ohms primary resistance, compatible with most C.D. ignition systems.