Genuine OEM HP Color LaserJet CM4540f MFP Toners
The Color LaserJet CM4540f MFP uses standard-yield HP 647A black toner. High-yield HP 646X black gives you more pages between changes; cyan, magenta, and yellow still use HP 646A. This is a black-capacity choice, not a different set of color supplies.
Toner Buzz carries genuine HP 647A and 646X black cartridges and individual 646A colors for the CM4540f MFP. Choose black capacity to suit how much you print, and order the color cartridges you need individually. Separate fuser, transfer, and toner-collection parts handle maintenance; the collection unit catches unused toner rather than supplying fresh toner.