Oki C5550 MFP User Manual page 233

W
ATERMARKS
A watermark is typically faint text that is superimposed on a
printed document. This can used to indicate that the document is
"Draft", or perhaps "Confidential".
The illustration below shows the Windows PostScript driver. The
PCL driver is very similar.
The Watermarks Feature is found in the driver's [Job Options]
tab. Click the [Watermarks] button.
PS Watermarks_oda.jpg
C5550 MFP User's Guide
A guide to printing > 233