The other end of the rails is marked as REAR
REAR.
3. Extend the mounting rails to align with the depth of the rack.
4. To install the mounting rails in a round-hole or square-hole rack, insert the pins on the mounting flanges into the rack post holes.
5. To install the mounting rails in a threaded round-hole rack, do the following:
a. Remove the pins and washers from the mounting rails.
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