Genuine OEM Volkswagen Three-Phase Alternator, part number 06K903023. This alternator is responsible for generating electrical current to power the vehicle's electrical systems and recharge the battery while the engine is running. It is mounted to the engine block. The alternator features a robust housing and precisely engineered internal components for efficient power output. Genuine OEM alternators are built to strict tolerances to ensure consistent voltage output and long service life, preventing electrical system failures.