Oki C3520 - Manual (Page 31)

Getting Started > 31
6. Close the cassette tray gently.
7. For face down printing, make sure the face up (rear)
stacker is closed (the paper exits from the top of the
printer). Stacking capacity is approximately 150 sheets,
depending on paper weight.
NOTE:
To prevent paper jams:
> Do not leave space between the paper and the guides
and rear stopper.
> Do not overfill the paper tray. Capacity depends on the
type of paper stock.
> Do not load damaged paper.
> Do not load paper of different sizes or types at the same
time.
> Do not pull the paper tray out during printing.
> Close the paper tray gently.