Cisco 12416 Installation And Configuration Manual page 302

Removing and Installing the Front Covers and Bezel Extenders on Original Cisco 12000 Series Routers
Figure 7-4
Captive screws
(2 on each side)
Be especially careful not to damage the honeycomb screen on the back of the air
Caution
filter door and on the inside of the switch fabric card cage. Damaging the
honeycomb screen can restrict the air flow and cause overheating in the router. It
can also diminish EMI protection.
Cisco 12016, Cisco 12416, and Cisco 12816 Router Installation and Configuration Guide
7-10
Opening the Chassis Air Filter Door
Switch fabric
card cage
(behind filter door)
Air filter door
Air filter
Chapter 7 Maintaining the Router
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