This Kit includes the MSD 6AL Digital Ignition Box, a SBC/BBC Pro Billet Distributor and 40,000 volt coil. The MSD 6AL box has built in rev limiter and is compatible with 4, 6 and 8 cylinder engines with 12 volt negative ground electrical systems. It delivers 530 volts to the coil with up to 135MJ of spark energy per firing. Rev limiter can be set in 100 RPM increments with two rotary dials and has built-in LED light for system checks. Box includes wiring harness, vibration mounts and all necessary installation components. Pro Billet distributor is machined from billet 6061-T6 aluminum on a state of-the-art CNC machine with exact tolerances. For high rpm stability, a .500" steel shaft is supported by a sealed ball bearing. 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 pick-up mounted in the housing. This high output magnetic pick-up is the most accurate way to trigger your ignition. Distributor also features an adjustable mechanical advance assembly and includes different springs and stop bushings so you can tune an advance curve to match your application. The Street Fire coil features low resistance and improved turn ratio producing a powerful spark for high performance.