This distributor uses a high-output magnetic trigger to fire an MSD Ignition Control. Accurate trigger signals and spark delivery are the responsibility of the QPQ-coated steel shaft. A sealed ball bearing and long sintered bushing hold this shaft stable at any rpm. An adjustable mechanical advance mechanism is mounted on top of the shaft. Nylon pads ensure smooth movement of the fine balanced weights for accurate timing advancement. A variety of advance stop bushings and springs are supplied so you can dial-in a custom curve.