HP Deskjet 6840 Color Inkjet Printer - Manual (Page 105)

Follow these steps to print collated copies:
1. Open the Printer Properties dialog box.
2. Click the Basics tab.
3. Type the number of copies that you want to print in the Copy count box.
4. Select the Collate check box.
5. Select any other print settings that you want, and then click OK.
8.8 Automatic two-sided printing
To print a two-sided document automatically, one of the following accessories must
be attached to the printer:
Automatic Two-Sided Printing Accessory
HP Deskjet 6800 series printer
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