The LEF-3L is a compact 3-call master station able to communicate with three other stations, plus selectively release doors and control external devices. CCTV cameras, lights, or other devices can be activated through a relay, which is triggered when a communication channel is selected. The master station is equipped with a door release button to activate electric strikes or magnetic locks.

A relay (RY-PA) is required for each external device and can be connected to provide a momentary or maintained closure. RY-PA has a “normally open” output, but can be modified to “normally closed”.