When you choose our Idler Pulley, you are investing in reliability and efficiency. Durable Front-Mounted Idler Pulley. Why Choose Our Durable Front-Mounted Idler Pulley?. Belt Type: Back Idler. Manufacturer Part Number: Idler and Belt Tensioner Pulley OE/OEM Part Number: Idler and Belt Tensioner Pulley Type: Idler Pulley Manufacturer : Idler and Belt Tensioner Pulley.