ACDelco ACK040378HD Professional Accessory Belt Drive System Tensioner Kit with Belt and Tensioner Does the job right the first time and reduces comebacks by always replacing the serpentine belt, idlers, and tensioners at the same time Has a lineup of parts that include 78 kits covering more than 1,300 vehicle applications for both import and domestic applications Includes a serpentine belt, idler(s), tensioner(s), and supporting hardware with detailed installation instructions Professional, premium aftermarket replacement Provides the performance and dependability you expect from ACDelco