Dell 3010cn Color Laser Printer - Manual (Page 32)

The center output tray holds up to:
l 250 sheets (20 lb (75 g/m 2 )) of plain paper: or
l 20 sheets of transparency: or
l 20 sheets of label: or
l 10 sheets of envelope
Using the Support Extension
The support extension is designed to prevent print media from falling from the printer after the print job is complete.
Before printing a document, make sure the paper extender is fully extended.