The LEF-3L is a surface mount open voice style master with door control ability. A maximum of 4 stations can be used in one system and any combination of doors and masters can be used to reach its maximum capacity. The LEF-3L is a compact, wall or desk mount master station able to selectively release a door or call up a camera. Used with any LE-(except LEF-3,5 and 10) or LS-series (North America only) remote station, communication can be established with each station by selecting the channel on the master station. While the channel is selected, pressing the door release button (left of TALK button) will release only the associated door. When used for camera call-up, a relay closure will be maintained as long as a station is selected. The system can have up to four stations, in any combination of masters or door stations (e.g. 2 masters and 2 doors). Master-to-master communication is also a standard feature.