Edelbrock Part 15039 Tensioner Upgrade Kit is engineered to handle the increased belt stress encountered in high horsepower E - Force applications. This kit is an upgrade for part 1573, 1576, 1592 1595 Edelbrock Supercharger systems produced prior to February 2013 and are now included on all systems thereafter. Kits includes tensioner, tensioner mounting bracket and hardware. Drive belt NOT included