First Alert Hard Wired Smoke and Fire Detector: Alarm is wired directly into your home's electrical system Includes battery backup to ensure alarm works during power outages Mute feature silences detector when nuisance alarm sounds Single button tests detector functions Includes adapter plugs to easily replace other detectors without rewiring Can integrate with up to 12 other First Alert or BRK hard wired alarms Easy-access battery drawer; no need to remove alarm from ceiling to change battery Includes manufacturer's 10-year limited warranty Meets UL standards Model# SA9120BPCN. Price: $16.97

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