Each precision CNC-machined billet aluminum housing features a sealed ball-bearing and long sintered bushing for stability at any rpm and increased endurance. An oversized steel shaft receives a QPQ coating to reduce friction and prevent corrosion. There is a big following of AMC enthusiasts that are cruising a 401 equipped Javelin or trailblazing in a rock crawling Jeep with a 4.0L inline 6-cylinder! MSD offers two Pro-Billet Distributors to deliver accurate trigger signals and are maintenance-free! This pick-up never requires adjustment and simply plugs right into an MSD Ignition Control. Just above it and under our strong race rotor is an adjustable mechanical advance assembly. The Chromoly weights of this assembly slide on nylon bushings producing smooth movement of the timing. You can easily adjust the curve to match your engine's requirements with the supplied springs and stop bushings. Both distributors are supplied with a high-quality cap, rotor, and gear. There is even a vacuum advance canister for street cruising economy!