VTech DM221-2 Manual - Manual (Page 10)

3
Getting started
Parent unit battery installation
You can power up the parent unit by connecting it to AC power or to the
rechargeable battery pack provided. Even if the parent unit is connected to
AC power, we recommend you also install the battery pack. This guarantees
continued operation in case of a power outage.
Install the battery as shown below.
Insert the battery into the battery compartment with the label
THIS SIDE UP facing up and the wires hanging out.
Plug the battery connector securely into the socket inside the battery
compartment. The parent unit turns on when it is powered up. Place the
wires neatly inside the battery compartment.
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