The Yale Smoke Detector allows you to Synchronise your home protection with your fire protection. Features (When used with SYNC ALARM range) When it detects smoke both the in-built siren and alarm will trigger. In built heat sensor that is visible in the app PIR Motion detection built in, activating the alarm when motion is detected and will work up to 200m away from the control panel. Inside the box 1 x Smoke Detector Batteries Fixing Pack Compatible with Yale Sync & Intruder Alarm Range (IA)