* No host,all alarms quickly achieve interconnection * .It contains a highly sensitive photoelectric smoke sensor,response quickly when excessive smoke have been detected * Remote control to interconnect all alarms quickly * Powered by 3years replaceable DC 3V AA alkaline or 10 years built-in lithium battery * The alarm volume is higher than 85 dB /3M,enough to wake you up when the danger comes * The Radio-frequency is 433 MHz * A variety of LED indications ensure normal operating * EN14604：2005 /BS5446-2:2003 certified product standards