Juniper Allegro CE Owner's Manual page 32

4) Slide the latches downward until they cannot slide any further to
securely latch the battery door closed.
Do not turn on the Allegro yet.
5) Plug the AC wall charger that came with the Allegro into the wall
socket.
The small green light on the wall charger turns on when it is
plugged in.
6) Remove the rubber protector from the Allegro's external power
input jack.
7) Plug the power connector end of the wall charger into the Allegro.
8) Charge the battery pack at room temperature until the charge
indicator on the Allegro turns off. This can take 3 to 5 hours the
first time you charge the battery.
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