Ritto 1273439 Comfort residential telephone with ED automatic door opener, white

For TwinBus door intercom systems with internal voice communication. Like residential telephone 1765070 but with additional automatic door opening via floor button. For automatic door opening via floor button, a call connection relay 17646 and a mains transformer 16476 are required. Door opener button. Light switching function via switching device. Radio transmitter board 17656 cannot be retrofitted. Color: white.