Description Reviews MINI Cooper S Idler Pulley by INA is just like the original but at a lower cost. This is a great replacement pulley when you need it. The only difference we can see is they didn't coat the pulley with a black hard coat, like the OEM one. It's an excellent pulley that we have been using here in the shop for a long time. It's proven to last as long as the original and save the customer money at the same time! This pulley comes with necessary hardware. This pulley is located on the belt tensioner and is responsible for maintaining tension on the serpentine belt and works. This pulley works together with the belt tensioner to maintain tension and guide the belt. Don’t neglect this often overlooked item that is incredibly important and easy to fix! Don't forget your belt tensioner while you're at it!