Features: The SALEM intercom set is intended for installation in single-family houses. The exterior panel is surface mounted, including a canopy, for direct power surge control. The power surge does not require an additional power source. The lighting and name space dimensions are 90 x 135 x 30 mm (width/height/depth). The Uniphone installation allows for 2 + 2 additional gate control and smooth adjustment of call volume to mute the intercom function after using an additional Uniphone. Dimensions are 105 x 210 x 26 mm (width/height/depth). The SALEM Intercom Set includes: outer cover (cassette) - 1, canopy - 1, Uniphone - 1, 18V DC DIN-rail power source - 1 pc.