Genuine OEM HP Deskjet 1120C Ink and Supplies
For the 1120C, the HP 45/23 ink combo pairs black with a tri-color cartridge. The HP 45 black twin pack serves a different purpose: both cartridges are black, so one can be kept as a spare.
Toner Buzz carries genuine HP 45 black and HP 23 tri-color ink as individual cartridges and in these packs. Choose the combo for both ink types together, or a single HP 23 when color is all you need.