H3C S5100-SI series Quick Start Manual page 41

Quick Start
H3C S5100-SI/EI Series Ethernet Switches
Note:
There are three positions to mount a load-bearing screw on both sides
of a switch. You should select a proper position according to the actual
requirements. The rear mounting ears tightly contacted with the
load-bearing screws can support the switch.
4) Select a position to install the switch and fix the rear
mounting ears to the rear brackets with screws and captive
nuts, as shown in Figure 3-7.
Figure 3-7 Fix rear mounting ears
Chapter 3 Installing the Switch
3-10
Rear square-holed rack