Canon Satera LBP-5600SE User Manual page 74

3
Place the stack of envelopes on a flat surface, flatten them to
release any remaining air, and be sure that the edges are
pressed tightly.
CAUTION
When loading paper, take care not to cut your hands with the edges of the
paper.
4
Loosen any stiff corners of the envelopes and flatten curls as
shown in the figure.
5
Align the edges of the envelopes on a flat surface.
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