Dell 1U Rackmount LED Console - Manual (Page 30)

26 xxx | Removal from the Rack xxx
To remove tooled rails:
1 Unscrew the two pairs of screws to detach the left and right brackets from
the front vertical rack flanges.
2 Unscrew the two pairs of screws to detach the left and right mounting rails
from the rear vertical rack flanges.
Figure 4.3. Removing Tooled Rails