SMOKE ALARM LIFESAFETY MODEL P9041 (No Radio Active Component) This product is a battery operated photoelectric smoke alarm, adopting unique structure design and advanced photoelectric sensor technology, able to monitor and detect smoke particles (associated with smouldering fire) sooner than ionization alarms. Once smoke particles or a fire danger is detected, this alarm will chirp and the red LED will flash rapidly to alert you and your family timely. Furthermore, this alarm has dustproof, mothproof and anti-light interface etc. functions, ensuring stability from design basis and suitable for early warning and protection of fires in houses, factories, shopping malls, hotels, office buildings, school buildings, banks, libraries and warehouses etc. indoor places.