Panasonic KX-TG5230C Operating Instructions Manual page 3

Expanding Your Phone
KX-TG5230C includes one handset and one base unit. You can expand the system
by adding up to 3 accessory handsets, sold separately.
A maximum of 4 handsets can be registered to the base unit.
The model numbers of the accessory handsets are KX-TGA520C and
KX-TGA523C. A charger is included with each accessory handset.
KX-TG5230C
The handset included is pre-registered at the factory and assigned the extension
number 1.
After purchasing accessory handsets, you must register each to the base unit.
(Please read the accessory handset's Installation Manual.)
Up to 3 accessory handsets can be added.
The illustration is KX-TGA520C.
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