Loren Cook 778531 Belt Tensioner is a mechanical component designed to maintain proper tension on drive belts in HVAC ventilation and air movement systems. It works by applying consistent pressure to the belt, reducing slippage and ensuring efficient power transfer between the motor and fan assembly. This belt tensioner is commonly used in Loren Cook fans, air handling units, exhaust ... https://www.partshnc.com/778531-loren-cook-belt-tensioner