This DPF (Diesel Particulate Filter) is for a Cummins ISX engine. NO CORE CHARGE. This item is new, never re-manufactured or re-conditioned. DPFs are tested against the OEM to ensure that backpressure, temperature, and the regeneration performance meets, or exceeds, the standards set out by the original manufacturer. This DPF is direct fit replacements for OEM systems to ensure that installation is as quick and easy as possible. Part includes all necessary ports and attachments for sensors and are designed to operate in the exact same capacity as the original OEM part. This DPF is backed with a 12 month warranty for any factory defects. See OEM numbers for direct match. ****Product cannot be sold or shipped to businesses or residents in California.**** Diesel Particulate Filters (DPF) are closed filters that remove diesel particulate mass (PM) and particulate number (PN) from exhaust gasses. Typically the regeneration process is controlled by the Engine Control Unit (ECU), which measures back pressure for the right data for regeneration. Regeneration is ensured by an exhaust temperature of around 570 - 750 degrees. The DPF use a unique mix of precious metals washcoat and substrate to turn soot into EPA acceptable exhaust.