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Lexmark 78C0D40 yellow developer unit cartridge in box

Lexmark

Lexmark 78C0D40 Yellow Developer Unit toner cartridges (genuine brands)

SKU CH-JK4Q-B0XZX MPN 78C0D40

Genuine Lexmark yellow developer unit works with Unison toner for laser printers and yields 125000 pages

  • Genuine Lexmark engineering ensures consistent image quality
  • Yellow developer unit works with Unison toner for reliable output
  • 125000 page yield reduces replacement frequency
  • Innovative shake-free print system simplifies operation
  • New condition guarantees full performance from first page

Genuine Lexmark Yellow Developer Unit

The Lexmark 78C0D40 is a genuine yellow developer unit designed for Lexmark laser printers. It works with Unison toner to deliver consistent image quality across high-volume print jobs. Offices and workgroups that rely on long-life reliability will find it matches the printer’s engineered print system.

Long-life reliability with shake-free operation

The developer unit supports a typical yield of 125000 pages, reducing replacement frequency in busy environments. Its shake-free print system maintains steady output without user intervention. The design promotes sustainable performance by extending the operational life of the print system.

Integrates with Lexmark print systems

This unit is built to function as part of the Lexmark print system, ensuring compatibility with the printer’s internal components. It frees IT staff from frequent consumable changes during large print runs. Buyers who need a colour outside the yellow channel or a toner cartridge rather than a developer unit should select the matching supply for their model.

Highlights

  • Genuine Lexmark engineering ensures consistent image quality
  • Yellow developer unit works with Unison toner for reliable output
  • 125000 page yield reduces replacement frequency
  • Innovative shake-free print system simplifies operation
  • New condition guarantees full performance from first page

Specifications

BrandLEXMARK
Shipping weight1.36 kg
Package size559 × 406 × 356 mm

Questions about this item

How do I install the Lexmark 78C0D40 Yellow Developer Unit without damaging the Unison toner interface?

Power off the printer, open the front cover, and remove the old developer unit by pulling its handle straight out. Align the new unit's rails with the printer guides, slide it in firmly until it clicks, then close the cover and power on. The shake-free design means no toner agitation is required.

When will the Lexmark 78C0D40 Yellow Developer Unit need replacement, and how do I know?

The unit is rated for 125000 pages. The printer will display a replacement warning when the end of life is reached. Replace it promptly to maintain consistent yellow output and protect the photoconductor.

What is the first limitation I will hit during long, continuous print runs with this developer unit?

The 125000-page yield is the primary limit. Under sustained high-volume printing, the developer's electrical properties degrade gradually, eventually causing faded yellow density or background toner before the printer signals replacement.

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