Dell EMC PowerSwitch Z9432F-ON Installation Manual page 20

6. Attach the outer rail to the front of the four-post rack. The rail clicks into place.
7. Repeat these steps for the second rail.
8. Slide the inner rails that are attached to the switch into the outer rails that are attached to the rails.
NOTE: Press the spring clip on each inner slide rail to allow the switch to slide into the outer rail.
20 Z9432F-ON switch installation