Ricoh Di-C1.5a Manual page 221

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Tray 1 can be replaced by an envelope feeder tray. (option)
The envelope feeder tray can handle ordinary paper;
however it is specially modified for smooth feeding of
envelopes.
Slide 221
No additional notes.
Envelope Feeder Tray
221
Di-C1.5 Training
Extra
feed
rollers