The HP DeskJet 2621 printer is compatible with HP 65 ink cartridges. It uses both the HP 65 Black Ink Cartridge and the HP 65 Tri-color Ink Cartridge. These cartridges are designed to deliver high-quality prints and provide consistent performance for everyday printing tasks. The black ink cartridge produces sharp text documents, while the tri-color cartridge ensures vibrant and accurate colors in images and graphics. These cartridges are easy to install and replace, allowing users to maintain the printer's optimal output quality.