The ACDelco Professional, premium aftermarket Automatic Belt Tensioner is designed for Accessory Belt Drive Systems (ABDS) that require an automatic belt tensioner. It ensures proper belt tension, alignment, and damping for superior performance and provides full line coverage for domestic, import, and heavy duty applications. Its patented vibration damping system increases tensioner, belt, and accessory component life and its torsional round spring design provides consistent tension and does not allow contamination. This premium aftermarket replacement automatic belt tensioner is manufactured to meet your expectations for fit, form, and function.