Brother HL-3400CN Series User Manual page 191

USER'S GUIDE
5-34
3. Adjust the Anchor Feet located at the rear and right hand side at the
bottom of the Lower Tray Unit to level the tray unit. The Anchor
Foot moves up and down as it is turned. Adjustment is completed
when the Anchor Foot touches the surface of the work surface and
the tray unit is level. Turn the lock screw to secure the Anchor Foot.
Fig. 5-38 Adjust the Anchor Foot
4. Remove both side covers from the Lower Tray Unit.
Fig. 5-39 Removing the Covers