This is a professionally remanufactured Epson T559420 yellow ink cartridge, originally an Epson T559420 / T5594 inkjet cartridge. It has been thoroughly cleaned, inspected, and refilled with the same ink formula to ensure reliable performance. The internal back pressure has been maintained, and the cartridge has undergone rigorous testing to meet quality standards. The original ink monitoring chip has been reset for accurate ink level readings. We offer a 100% Quality Satisfaction Guarantee on this remanufactured T559420 yellow ink cartridge.