Dell 5535dn Mono Laser MFP - Manual (Page 77)

Without an optional StapleSmart II Finisher With an optional StapleSmart II Finisher
Duplex (two-sided) printing Duplex (two-sided) printing
Note: Notice the maximum fill line on the side of the tray which indicates the maximum height for loading paper.
Do not overload the tray.
7 Insert the tray.
Loading paper and specialty media
77