Illuminate your path to safety with the First Alert® SM210L Sealed 10-Year-Battery Smoke Alarm with Safety Path Light. The SM210L smoke alarm also features our Precision Detection advanced sensing technology. It complies with the latest industry standards to reduce cooking nuisance alarms and provides early warning in the event of a home fire emergency. The smoke detector also has a slim profile, measuring only half the depth of a standard alarm. Its sleek, modern design seamlessly blends into most décor and is easy to install throughout your home. And the 10-year lithium battery means no battery replacements for a decade – the end-of-life warning lets you know when it is time to replace the alarm.