Canon imageCLASS MF4270 Basic Operation Manual page 71

3
Slide the paper guides so that they fit to both sides of the paper.
If the paper guides do not fit the size of the paper, the print quality may be deteriorated.
4
Specify the size and the type of the paper you load.
For details on how to specify the paper size and type, see "Setting Paper Size and Type, " on p. 2-15.
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