Dell 1U Rackmount LED Console - Manual (Page 9)

Installation xxx | xxx 5
Preparing to install tooled rails:
1 Remove the screw from the front mounting bracket using a torx-head
screwdriver, then remove the pins from the front and rear mounting brackets
using a flat-tipped screwdriver.
2 Pull and rotate the rail latch subassemblies to remove them from the
mounting brackets.
Figure 2.2. Preparing to Install Tooled Rails