Dell C2665dnf Color Laser Printer - Manual (Page 305)

Envelope #10, Monarch, or DL
Load the envelopes short edge feed with the flaps closed and the print side up. Ensure that the flaps come at the left
when you face towards the printer.
C5
Load the envelopes short edge feed with the flaps open or closed and the print side up.
Ensure that the flaps come at the bottom with the flaps open or at the top with the flaps closed when you face
towards the printer.
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