First Alert SC9120LBL Smoke and Carbon Monoxide Alarm, 85 dB, Electrochemical Sensor

The First Alert SC9120LBL hardwired combination smoke/CO alarm connects directly to your home electrical system. In the event of a power outage, the smoke/CO alarm is equipped with a 10 years lithium battery backup. Integrating a smart technology system will reduce the likelihood of nuisance alarms triggering. A latching alarm Indication will remember which unit initiated an alarm. The perfect mount system features a gasket less base and a mounting bracket that keeps the alarm secure over a wide rotation range to allow for true alignment. Under normal conditions, you should not have to replace the battery for the life of the alarm.