This remanufactured HP 51640A black inkjet cartridge is an original Hewlett Packard cartridge that has been cleaned, inspected, and refilled using both OEM and non-OEM components. It features a professionally manufactured pigment-based ink formula designed for archival print life and color stability, ensuring vibrant and long-lasting prints. Each cartridge undergoes rigorous testing to guarantee quality and reliability, backed by our 100% Satisfaction Guarantee. Please note that this cartridge is not remanufactured by HP.