HP Deskjet 6840 Color Inkjet Printer - Manual (Page 177)

Note: The Auto Two-Sided Print Accessory with Small Paper Tray is not available
in all countries/regions.
12.3.1 Installing the Auto Two-Sided Print Accessory with Small Paper
Tray
Use these steps to install the Auto Two-Sided Print Accessory with Small Paper
Tray:
1. Push the two latch handles on the printer rear access door toward each other,
and then remove the door.
Do not discard the rear access door. In order to print, the accessory or the rear
access door must be attached to the printer.
2. Insert the accessory into the back of the printer until both sides snap into place.
Note: Do not press the buttons on either side of the accessory when
installing it into the printer. Use the buttons only when removing the
accessory from the printer.
HP Deskjet 6800 series printer
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