Hitachi GR4000 Series Installation Manual page 209

Step 3
the figure below. (The network interface board will come out 15mm or so towards you.)
Lever
Figure 5.7-2 Network interface board unlocked
*
*
520-10-014-20X
Open the small levers (not the big ones) towards the direction indicated in
NOTE: When removing a network interface board from the slot, do it holding its levers
so that its connector part is detached smoothly. When moving levers, do it
slowly without giving much pressure to them.
NOTE: The big levers, which are located under the small ones, are not used for the
purpose of unlocking a network interface board, therefore do not try to open
them forcibly.
GR4000 Installation Guide Version 1.00 - Preliminary
Lever
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