Brennenstuhl smoke alarms white brennenstuhl 1290020 this smoke alarm br 1211 interlink from brennenstuhl has been designed to offer more safety for your family and property courtesy of the photoelectric detector which has been tested in accordance with en 14604 equipped with a host of excellent features including the bi directional radio system for sending and receiving for a wireless radio networking of up to 12 smoke detectors plus 16 radio channels where coding prevents interference