FIRST ALERT FAT1039746 CO615 Dual Power Carbon Monoxide Plug in Alarm w Display Category_Carpets and Liners Frequency Response: 60 4000Hz Category_Marine Stereos Frequency Response: 60 4000Hz Rescue Throw Bag With Adjustable Strap And 3M Reflective Exterior Safety Band even in the event of a power outage Model number CO615Dual power carbon monoxide alarm offers continuous monitoring of carbon monoxide levelsPlugs into any outlet & features battery backupBacklit digital display shows readings for power & carbon monoxideSingle test silence button for simple operationEnd of life timer signals when the detector needs replacing7 year limited warrantyIncludes 2 AA batteries