Functions:
To talk with door station
To unlock for door station
To call guard unit
To connect with door bell
To connect with one extension indoor phone at most
Technical parameters:
Audio S/N: >=30dB
Audio distortion: <=7%
Environment temperature: -10 to +55 degree Celsius
Dimensions: 106 x 200 x 60mm
Installation: surface mount
indoor phone F-6 used in intercom system ,CE certificate,