Genuine OEM HP DeskJet 890 Cse Ink and Supplies
The 890Cse uses HP 45 black and HP 23 tri-color ink. An HP 45 twin pack contains two black cartridges; the 45/23 combo contains one black and one color cartridge, so pack size alone doesn't tell you which inks you're buying.
Toner Buzz carries genuine HP 45 and HP 23 singles and both pack types. Choose the black twin for a spare HP 45, or the combo when you need black and tri-color ink together.