The S series of 6 phase alternators offers incredible low RPM output in a compact and durable package. Highly efficient, these units use less horsepower than conventional 3 phase alternators. 12 diodes, twin rectifier plates and outstanding airflow ensure long service life, even in severe conditions. This unit is specially designed to replace CS130 alternators with 6.15 inch center-to-center distance bolt patterns, as used by several aftermarket accessory drive manufacturers. This unit includes a specially machined March performance 6 groove serpentine pulley, fan, and decorative cover already custom fitted to the alternator. A single wire on the provided pigtail gets connected to any ignition switched 12V+ source to turn the alternator on and off with the ignition switch. Simply run a properly sized positive and ground cable from the alternator to the terminals of the battery and the alternator will work perfectly, regardless of what kind of wiring harness you have.The 1.75 inch diameter pulley on this unit will yield 140+ amps at just 800 engine idle RPM with a 6 inch crankshaft pulley. Be sure to calculate your pulley ratio for high RPM or racing applications to ensure the alternator is not over-spun when at high engine RPM.