This is MSD's most popular performance distributor. The housing is machined from a billet of 6061-T6 aluminum on a state-of-the-art CNC-machine producing exact tolerances. For high RPM stability, a .500" steel shaft is supported by a sealed ball bearing and a long sintered bushing. This shaft also receives a QPQ coating for friction reduction and resistance to corrosion. A precision machined reluctor is attached to the shaft which triggers the magnetic pickup mounted in the housing. This high output magnetic pickup is the most accurate way to trigger your ignition.