Canon PIXM MX300 Series User Manual page 210

Recommended printing area
Printable area
Envelopes
Size
European DL*
US Comm. Env. #10*
* Envelopes can be used only when printing from your computer.
Printable Area (width x height)
4.06 x 7.12 inches / 103.2 x 180.8 mm
3.86 x 7.96 inches / 98.0 x 202.1 mm
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