This smoke alarm is part of the Visit smart home system that helps you to secure your home. It discovers smoke and smoldering fire at an early stage and relays the alarm directly to your Visit receiver, so you can get out of harm's way in time. Type: Optical Features Safe at Night - Relays the alarm to your bedroom. Long Lasting Power - Up to 10 years battery life. Silence Function - To avoid nuisance alarms. Reliable Connection - Up to 250 m operating range. In the box Smoke Alarm Screws Batteries