/PDFPREF 1

Tool bar is hidden when the PDF document is opened.

/PDFPREF 2

Menu bar is hidden when the PDF document is opened.

/PDFPREF 4

User interface elements associated with the document window (e.g. scroll bars) are hidden leaving only the document's contents displayed.

/PDFPREF 8

Resize the window to fit the first page.

/PDFPREF 16

Window placed in the center of the screen.

/PDFPREF 32

Document title is merged into the main title bar; filename no longer displayed.

/PDFPREF 64

"Full screen mode". Press "Esc" key to revert to normal view.

/PDFPREF 128

Page scaled to fit width of window.

/PDFPREF 256

Page scaled to fit height of window.

/PDFPREF 384

128 + 256 = 384 results in the width and height of the page being scaled by the same percentage so that one page fills the full width or height.