Kidde Hardwired SmokeCarbon Monoxide Detector, AA Battery Backup, Voice Alerts, Interconnectable, LED Warning Light Indicators, 2 Pack

2-in-1 Detection Smokecarbon monoxide detector combo alerts you to both smokefire events as well as poisonous, CO gas in a single device, Voice Alarm announces the hazard type when detected: "Fire. " = smoke or fire, "Warning Carbon Monoxide" = CO gas, or "Low Battery" when the batteries need to be replaced, 85-decibel alarm alerts to smoke, fire, or carbon monoxide, 24/7 Self-testing components are always checking the device to ensure it's operating as expected (not a substitute for a manual push test, Whole-Home Alarm Activation expands detection via hardwired connections to other Kidde smoke alarms, so when 1 alarm sounds, they all do**, Easy Installation Mounting bracket included for quick installation in 4 orientations, 120V AC hardwired with 2-AA battery backup (includedprovides reliable protection, even during power failures, UL Listed with a 10-year limited which begins when the alarm is powered on, if that date is unknown it should be assumed the alarm should be replaced.