Brother MFC-3240C - Manual (Page 20)

1 - 12 USING THE MACHINE AS A PRINTER
Paper Size
The Paper Size selection provides a large selection of standard
paper sizes. If you wish, you can create a custom size ranging from
3.5" x
5" (88.9 x 127.0 mm) to 8.5" x 14" (215.9 x 355.6 mm). Also
you can select borderless setting for specific papers. From the
drop-down box, select the Paper Size you are using.
You can enter a custom size by selecting User Defined. Select the
correct paper thickness to improve the quality of your output.