These MSD Pro Mag 44 electronic points boxes are responsible for controlling the Pro Mag 44's energy, such as the special long duration spark and quick rise time. They feature electronic circuitry that replaces the breaker points. This allows the power of the generator to be released to the coil instantly and at full power. The boxes keep the electricity flowing across the plug for a full 26 degrees of crankshaft rotation, ensuring complete combustion, and they are available with an optional rev limiter.