Our Idler Belt Pulleys are engineered to effectively route the serpentine belt for proper alignment with the accessory drive belt. Product Features:Steel or plastic construction for long-lasting durability against heat, shock and corrosionReplacement stops squeak, squeal or groaning noise associated with a worn idler pulleyDirect replacement and direct fit idler pulleys for a trouble-free replacementVehicle try-on testing and rigorous materials testing to ensure high-quality performance