Fujitsu PRIMERGY BX620 S4 Options Manual page 50

Storage Module Variants
To install a BBU card in the storage module, proceed as follows:
Figure 31: Installing the RoMB Activation Key
Ê Place the RoMB activation key into the round socket (arrow).
V
CAUTION!
The labeling of the RoMB activation key must must face upward.
50 Options Guide
Storage Modules
BX620 S4