Product Details: The Dayco Serpentine Automatic Belt Tensioner is designed to provide reliable and efficient performance. This tensioner features a steel pivot tube on specific designs for enhanced stability, zinc coated mounting bolts that resist rust, and thermoplastic rubber spring slot plugs and rubber O-ring seals to help keep contaminants out. It is designed for counter clockwise rotation and is compatible with serpentine belts with a pulley diameter of 60mm. FleetPride is your First Click in Heavy Duty®.