Panasonic Toughbook CF-19AHJAX1M Reference Manual page 48

Battery Power
To insert
Insert the battery pack until it securely fits the connector.
A
Close the cover until it clicks.
B
Slide the latch (C) to the left to lock the cover.
C
CAUTION
Make sure the latch is securely locked, otherwise the battery pack may fall when you carry the computer.
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