Fujitsu FI-5530C2 Operator's Manual page 24

HINT
HINT
8
Before placing the document, pull out the ADF paper chute extension
depending on the lengths of the document.
Place the document so that the height of the document will not surpass the
line mark located at the side guide.
For A4-size paper or smaller, place the document so that the height of the
document will not surpass the [Letter/A4/Smaller] line mark.
For paper larger than A4 size, place the document so that the height of the
document will not surpass the [Over Letter/A4 Size] line mark.
Extension