The Kenworth 3S Flex Exhaust Bellow is designed for OEM Number M66-6542-0320 and fits most Kenworth models. This exhaust bellow features a natural finish and is sold individually. It is a practical and reliable solution for replacing worn-out or damaged exhaust bellows, offering a perfect fit for OEM and aftermarket numbers M66-6542-0320 and M6665420320. With its durable construction and easy installation, this exhaust bellow provides a cost-effective and efficient solution for maintaining the performance of your Kenworth vehicle.