Genuine OEM HP DeskJet 722 C Ink and Supplies
The 722C's HP 23 cartridge holds cyan, magenta and yellow together. That means the HP 45/23 combo covers black and color with one cartridge of each type, rather than four separate tanks.
Toner Buzz carries genuine HP 45 black and HP 23 tri-color singles, the 45/23 combo and a black twin pack. The combo suits a black-and-color purchase; the twin pack gives you an extra HP 45 to keep on hand.