Dell PowerEdge 4220 Guide D'installation page 36

5 Install the coupling brackets.
Position the two racks side by side.
a
Adjust the leveling feet on both racks so that the racks are parallel
b
and in the same horizontal plane. For instructions, see "Adjusting the
Leveling Feet" on page 24.
To install the coupling brackets on the racks, hook the brackets into
c
the square holes inside and adjacent to the rack posts, and tighten the
brackets using the wingnuts (see Figure 1-21).
Figure 1-21. Coupling Two Racks
3
1 coupling bracket locations
3 coupling bracket (4)
34
Installation Guide
2
2 wingnut
1