Canon Color ImageRunner C3380 Reference Manual page 367

If you are using ISO-B5, ISO-C5, COM10 No.10, Monarch: Catalog Glove No.8,
or DL envelopes, hold down the four corners of the envelopes firmly, so that they
and the sealed or glued portion stay flat.
If you are using Yougata 4 envelopes, load the envelopes without folding them.
IMPORTANT
•
If you use envelopes that have glue attached to their flaps, the glue may melt due to
the heat and pressure of the fixing unit.
•
Take particular care to spread the envelopes out in the direction that they will be
fed.
•
Do not print on the back side of the envelopes (the side with the flap).
•
If the envelopes become filled with air, flatten them by hand before loading them
into the envelope feeder attachment.
Flap
Flap
Envelope Feeder Attachment-C2 (Optional)
7
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