ACDelco 334-1721 Professional Alternator, Remanufactured Remanufactured using consistent quality processes; not just rebuilt Alternators use high-quality bearings with high-temp lubricant and double-lipped rubber seals, reducing friction, vibration, and noise Rotors and stators are electronically tested and then sealed with secondary insulating coating to help prevent shorts Performance-tested and inspected to ensure they meet your expectations for quality design and component specifications