Cisco ASR 901S Series Installation Manual page 59

Installing the Router
Opening the Router Cover
It is recommended that you loosen and tighten the captive screws in the order as shown in the following figure.
Figure 27: Recommended Order of Loosening and Tightening Captive Screws
The chassis cover features an environmental seal that protects the chassis against environmental elements
when the cover is closed. This seal creates pressure, which can cause the cover to open suddenly when the
last screw is loosened.
Materials Required
Special screw driver (available as part of the accessories/install kit)
Cisco ASR 901S Series Aggregation Services Router Hardware Installation Guide
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