This part is a replacement idler pulley. This is a genuine OEM part made by MTD and has been sourced directly from the manufacturer. This part can be used to replace a defective or broken idler pulley in a variety of lawn tractor models. Idler pulleys help to guide the engine's drive belt. This part is subject to significant wear and tear over time and may require replacement. Signs that the idler pulley might need replacing include a squealing sound coming from the belt or the pulley being visibly worn. Proper tools are required to install this part. It is always recommended that the appropriate safety precautions are adhered to when attempting to fix any power tools or machinery. For more accurate information on how and where to install this idler pulley, the appropriate owner's manual and included diagrams should be referenced.As an authentic replacement part, this idler pulley is suitable for use on several different models of lawn tractors manufactured by MTD, Troy-Bilt, Yard Machines, Cub Cadet, Husky, and Yard Man. This is a genuine part made of high-quality, durable materials and is sold individually.