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Rectangular grey duplexer unit with paper path rollers and side latches

HP Publishing

HP Publishing Duplexer Assembly Q2439B for LaserJet 4240/4250/4350

SKU CH-CK3J-YQ20Y

Adds automatic two-sided printing to compatible LaserJet 4240, 4250 and 4350 printers

  • Product SortPrinter Accessories
  • Product TypeOther Accessories
  • Enables automatic two-sided printing on compatible LaserJet models
  • Designed for LaserJet 4240, 4250 and 4350 series printers
  • Restored to original manufacturer specifications for reliable operation
  • Includes 90-day depot warranty for added confidence
  • Professionally packed to prevent damage during transit

HP LaserJet Duplexer Q2439B

This genuine HP duplexer assembly adds automatic two-sided printing to LaserJet 4240 4250 and 4350 series printers. The unit installs in the standard rear accessory slot and handles paper feeding for duplex output without user intervention. It is supplied new and ready for immediate installation.

For offices printing double-sided documents

Teams that regularly produce two-sided reports invoices or letterhead will benefit from the hands-free operation this accessory provides. Sites that only ever print single-sided pages or that use a different printer family will not need this assembly.

Part number Q2439B confirms compatibility

The assembly is built to the Q2439B specification and fits the LaserJet 4240 4250 and 4350 model ranges listed in the manufacturer data. Verifying this exact part number against the printer label is the single step that ensures the unit will mount and function correctly.

Highlights

  • Enables automatic two-sided printing on compatible LaserJet models
  • Designed for LaserJet 4240, 4250 and 4350 series printers
  • Restored to original manufacturer specifications for reliable operation
  • Includes 90-day depot warranty for added confidence
  • Professionally packed to prevent damage during transit

Specifications

Product SortPrinter Accessories
Product TypeOther Accessories

Questions about this item

Which HP LaserJet models accept the Q2439B duplexer assembly?

The assembly fits LaserJet 4240, 4240n, 4250, 4250DTN, 4250DTNSL, 4250N, 4250TN, 4250Xi, 4350, 4350DTN, 4350DTNSL, 4350N, 4350TN and 4350Xi printers.

Does the duplexer require any firmware update on a LaserJet 4250DTN already in use?

No firmware change is needed; the unit installs directly into the printer's duplex slot and is recognised automatically.

How can I confirm the duplexer is operating correctly after installation?

Print a two-sided test page; if both sides feed and print without jam, the assembly is working as intended.

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