Dayco No Slack Automatic Belt Tensioners are built to outperform and outlast competitive OE parts. This specific Dayco Automatic Belt Tensioner is manufactured with a specially coated patented flat wire spring to allow the internal tension to be concentric, thus providing a more even degree of constant tension. The heavy duty cast aluminum spring case resists cracking and fatigue. Each component is built to resist rust, endure the toughest of conditions while promoting quieter performance and longer life. This being an integral tensioner, the required plastic elbows & o-rings are included. Product Features:Manufactured with a specially coated patented flat wire spring to allow the internal tension to be concentric, thus providing a more even degree of constant tensionThe heavy duty cast aluminum spring case resists cracking and fatigueThe required plastic elbows & o-rings are included