Wired interconnect smoke alarms THC-SO-929 Features Wire Interconnected Smoke Alarm Inter linkable smoke alarm 220V or 110V AC plus 9V Battery Operated Hush Button - Mute False Alarm Infrared photoelectric sensor MCU processing Auto reset after smoke clears Sound and flash alarm LED indicator Test and hush button Low battery indication Dustproof , mothproof and anti-white light design Technical data Battery DC9V or AC110V, 220V Alarm Sound more than 85db 3m Static Current less than 10 Mu A Alarm Current less than 10 mA Low Voltage Alarm 7V+-0.5V Work Temperature -5 to +40 degrees Working Humidity less than 93 percent RH Low Battery Alarm Remain 7 to 15 days IP Rating IP20