Printer features: Which component enables an office printer to automatically print on both sides of the paper (duplex printing)?

Introduction / Context:
Duplex printing saves paper by printing on both sides automatically. Identifying the printer subsystem responsible for flipping or re-feeding sheets is a common certification and support question.

Given Data / Assumptions:

• We are discussing standard office laser/inkjet printers.
• Goal: automatic two-sided printing without manual page re-insertion.
• Mechanical modules add or route media during the print path.

Concept / Approach:

The duplexer is a mechanical module that reverses and re-feeds the paper so the device can print the second side. It may be internal or an external accessory. Other subsystems, such as the fuser and toner cartridge, handle image formation and fixing—not sheet inversion.

Step-by-Step Solution:

Verification / Alternative check:

Printer specs list “auto duplex” or “duplexer included/optional.” Enabling duplex in driver settings works only when the hardware duplexer is present and configured.

Why Other Options Are Wrong:

• Fuser: Heats and bonds toner; does not flip pages.
• Toner cartridge: Supplies toner; no page inversion role.
• Paper-swapping unit: Not a standard term; duplexer is the correct name.
• None of the above: Incorrect because duplexer is correct.

Common Pitfalls:

Confusing manual duplex (user flips) with automatic duplex; assuming driver setting alone guarantees duplexing without the hardware module.

Final Answer:

duplexer