3Com CoreBuilder 9000 Getting Started Manual page 37

To install the OC-12c/STM-4 card in the left cutout, perform the following
procedure:
1 Hold the card with the beige bridge connector facing downward and the
protective plugs facing forward.
2 Hold the card at a ~20° angle to the horizontal and insert the card into
the left cutout from the back of the ATM Interface Carrier Module
(Figure 16). Make sure that the RFI shield has not moved.
Figure 16 Inserting the OC-12c/STM-4 Card into the Cutouts
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3 Lower the OC-12c/STM-4 card until its beige bridge connector is aligned
over the beige bridge connector of the ATM Interface Carrier Module.
Installing the OC-12c/STM-4 Daughter Card 37