First Alert SMCO500V Interconnect Battery-Operated 2-in-1 Smoke and CO Alarm with Voice and Location Alerts, 1048446

First Alert's Precision Detection advanced sensing technology complies with new industry standards to reduce cooking nuisance alarms and provides early warning in the event of a home fire emergency Through early warning interconnect, when one alarm sounds, all compatible alarms will sound Battery-operated alarm is easy to install and maintain Provides reliable 2-in-1 protection against both smoke and carbon monoxide