www.libertyhealthandsafety.com
DSI-VC3 phones (UT4140) are only to be used as a part of a PBX based phone system
and NOT to be used on a PSTN.
PBX models such as:
NEC models: SV8100, SV8300, SV8500, SV9100, SV9300, SV9500
Panasonic models: KX-TDE100, KX-TDE200 and KX-TDE600
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