Panasonic KX-TDA0103 L-Type Power Supply is compatible with KX-TDA200, KX-TDA600, KX-TDE200 KX-TDE600
It a large plug-in system power supply for use in the main cabinet of the KX-TDA100 KX-TDE200 as well as the main cabinet and expansion cabinets (KX-TDE620 or KX-TDA620) of the KX-TDA600 KX-TDE600
The KX-TDA200 KX-TDE200 and KX-TDA600 KX-TDE600 Systems will not work without a power supply
KX-TDA600 KX-TDE600 Systems also require a BUS-M and BUS-ME when expanding to additional cabinets
You can the correct size power for a Panasonic Phone System by referring to Power Supply Sizing Chart.