connection to the control panel two-wire line cooperates with CYFRAL intercom panels type TD3, TD4, TD6; CC-1000/1500 function keys placed on the base next to the headphone 1 button – door opening function 2 button – multi-functional for example for lighting possibility of starting an electro-trailer without lifting the headphone control of call volume with off chat secrecy – no wiretap between the tenants, the possibility of simple conversion of the camera to the listening version (jumper) installation of cables without soldering power from the door control unit