Oki C7100 User Manual page 30

5. For face down printing, make sure the rear paper exit is closed
(the paper exits from the top of the printer). Paper is stacked in
printed order and paper tray capacity is approximately 500
sheets, depending on paper weight.
6. For face up printing, make sure the rear paper exit is open and
the paper support is extended. Paper is stacked in reverse
order and tray capacity is approximately 100 sheets,
depending on paper weight.
Don't open or close the rear paper exit while printing as it may result in
a paper jam.
Always use the rear stacker for thick paper (card stock etc.)
7. Load letter headed paper face down as shown for both portrait
and landscape:
CAUTION!
NOTE
SETTING UP > 30