Philips Hue Secure Smart Contact Sensor, White – 1 Pack – Made for Indoor Doors and Windows – Requires Hue Bridge – Works with The Hue App

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SECURITY THAT WORKS WITH YOUR PHILIPS HUE LIGHTS: Hue Secure sensors integrate seamlessly with your existing Philips Hue lights; When motion is detected, your lights can turn on automatically.
STAY IN THE KNOW, WHEREVER YOU ARE: Get real-time motion notifications sent directly to your phone. Trigger alarms right from the Hue app.
ONE APP, COMPLETE CONTROL: Control your Hue lights, cameras, sensors, and security notifications from a single app. The Hue app puts your entire smart home security system in the palm of your hand.
AUTOMATE YOUR LIGHTS – The contact sensor is perfect for frequently used areas. Have the hallway light turn on when the front door opens, for example.