First Alert BRK 9120LBL Hardwired Smoke Detector with Adapter Plugs for Easy Replacement

This hardwired First Alert smoke alarm includes a 10-year battery backup for constant monitoring during the life of the alarm, even if there's a power failure. Includes convenient adapter plugs that allow for you to easily replace existing hardwired alarms without needing to rewire.The alarm features an ionization sensor for detection of smoke and fast-flaming fires, as well as a loud, 85-decibel alarm. One button silences any nuisance alarms, and also tests functions, while lights indicate if the alarm detects smoke. And an end-of-life signal enhances your safety by letting you know when it's time to replace the unit. Connect it to compatible BRK or First Alert alarms within a single-family residence. When one alarm is triggered, all connected alarms will sound.