The HP No. 81 Dye Ink Cartridges are part of a modular ink system that delivers fast printing automatically. Experience the widest color gamut and smoothest color transitions offered by HP large-format printers with HP No. 81 Dye six-color ink system and newly formulated dye-based inks. "Smart chips" embedded in each of the HP No. 81 Dye ink cartridges and printheads monitor ink usage and track printhead wear, and alert you when it's time to replace. HP No. 81 ink supplies are HP engineered and tested to work precisely with HP DesignJet 5000 Series printers and compatible HP printing material to deliver the professional results you expect.