Add on phone for Two Way Ring Down Circuit. Needs a RJ-11 splitter to add more phones.

Controller unit enables two standard telephones to be used as an intercom system.

Provides basic master to substation intercom communication using handsets. 1 master and up to three substations. Either battery or AC powered.

Provides basic master to substation intercom communication using handsets. 1 master and up to three substations. Either battery or AC powered.