Dell 5230 User Manual page 59

Without an optional Staple Finisher
Single-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.
With an optional Staple Finisher
Single-sided printing
Duplex (two-sided) printing
Loading paper and specialty media
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