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 much better durability than standard Delco CS130 based alternators. even in severe conditions. This custom designed housing directly replaces standard CS130 "left mount" alternators as used on 1987-1995 Chevy C1500 Pickups and some aftermarket accessory drives. A side output stud and seamless rear cover with no plug opening allow for better clearance from the back of the alternator to the front of the engine and a smooth appearance. A "one-wire" self exciting internal voltage regulator makes installation of these alternators on older or customized vehicles a snap- 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. Because of their compact size and standard GM mounting ears. these alternators also work well in many aftermarket or custom bracket installations.