Kyocera Mita FS-1800/N User Manual page 257

Printing through Application Software
6
Click the Properties button in the Print dialog box. The Properties
dialog box is displayed.
7
Click the paper size icon in the Paper Size list box so that it is
greyed, then click the OK button. A5 was selected for the following
example.
When printing using non-standard size paper, see
Size Settings on page 3-4.
3-2
3.1.1 Custom