The Greenbox Replacement Ink Cartridges two BK1x30ml and C/M/Y 3x12ml are designed for use with Deskjet and Officejet printers. These remanufactured cartridges use inkjet print technology and come in tri-color and black colors. The cartridges are compatible with the HP 61 model and are manufactured in China. With Greenbox ink cartridges, you can expect high-quality prints and reliable performance for your printing needs.