Other Hp 19A Original Drum Unit(CF219A)

The HP 19A (CF219A) is an imaging drum unit for HP LaserJet printers — not a toner powder cartridge itself. In HP laser printers the imaging drum is a separate component that works together with the toner cartridge to transfer toner onto paper during printing

 Functions 

• The toner cartridge holds the toner powder used for printing.
• The imaging drum (19A) receives an electrostatic image from the laser, which picks up toner and transfers it to paper.  
• When the drum wears out, print quality drops (usually fading or streaks), so it’s replaced separately from the toner.