IBM G8000 Installation Manual page 47

Foam
M4
Card guides
thumbscrews
Side flanges
7. Use the two M4 thumbscrews to secure the air duct unit to the air duct brackets.
For information about removing the air duct, see "Removing the 1U air duct option"
on page 41.
31
Chapter 2. Installing the RackSwitch and options