HP Deskjet 6620 Color Inkjet Printer - Manual (Page 15)

3. Slide the photo/envelope feeder forward as far as it will go.
4. Print the postcard .
4.6 Print cartridges
Four print cartridges are available for use with the printer.
1. Black
2. Tri-color
3. Photo
4. Gray photo
Note: The availability of print cartridges varies by country/region.
HP Deskjet 6600 series printer User's Guide
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