The 12 Inch Cummins ISM Diesel Oxidation Catalysts with a 13.17 Inch Diameter are designed for high durability and effectiveness, reducing backpressure and fuel consumption. Manufactured according to OE technology, these catalysts are made to match OE performance and fit most Cummins ISM makes and models. With a stainless steel construction and exhaust emission norm of EPA07, these catalysts come with clamps and gaskets included for easy installation. They are a practical and environmentally friendly choice, providing a direct OE replacement for various OE numbers, making them a convenient option for diesel vehicle owners.