The Peterbilt 365, 387, and 388 2008 through 2011 Bellow Pipe Kit is a reliable and durable solution for preventing exhaust leaks and maintaining engine efficiency. This kit includes a 3.25-inch inside diameter exhaust bellow, along with two clamps and two gaskets for a complete installation. Engineered in North America with high-quality materials, this direct replacement flex pipe is designed to fit and function like the original, ensuring proper performance. Tested for vehicle fitment and material quality, it is a trustworthy choice for Peterbilt 365, 387, and 388 models with ISM 10.8, ISX 11.9, and ISX15.0 engines. Direct OE replacement numbers are Paccar M66-3161-0390 and M66-7091-0405.