This is a rebuild replacement injection pump for your Chevrolet GMC 6.6l Duramax applications, 2001 thru 2006. This is a direct replacement for the unit on the vehicle. it has been fully rebuild with the latest updates provided by Chevrolet. This is a remanufactured part and comes with a one year, unlimited mileage warranty. This unit is sold exchange and we must either have your old unit prior to shipment, or you can contact us to make arrangements for the return of the core.