Konica Minolta QMS magicolor CX Reference - Manual (Page 84)

The Envelope
Cassette
QMS magicolor CX Reference Guide 2-10
3 Set the envelope-size key to the correct envelope size.
4 Lift the stacker arm and load 30 or fewer envelopes printing-
side up, so that the flap side will be on the left when the
envelope is pulled into the printer.
5 Lower the stacker arm.
Flap Side