Dell S4048T-ON Guide De Mise En Route page 16

Four-Post Threaded Configuration
To install the Dell ReadyRails system using the four-post threaded
configuration, follow these steps.
1. For this configuration, remove the flange ear castings from each end of
the ReadyRails assemblies. Use a Torx driver to remove the two screws
from each flange ear and remove each casting. See item 1 of the
following figure. Retain the castings for future rack requirements.
2. For each rail, attach the front and rear flanges to the post flanges with
two user-supplied screws at each end. See item 2 of the following figure.
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