This compact, surface-mounting, internal video unit with colour screen is delivered standard equipped to perform the following functions: allow a conversation with a visitor, produce a different tone for a call at an apartment door, main door or an internal call, switch lights on and off, open doors, adjust the volume and image, switch off the ring tone, activate the camera, indicate a busy signal and call signal with LEDs, transmit a control function (for relay 10-831 and others), allow a parallel call, make an internal call, etc. It is operated using touch-sensitive keys and a menu which appears on the screen. The communication with the visitor is hands-free.