Ring Alarm Contact Sensor (2nd Generation)
Cover all your windows and doors: A Ring Alarm 5-piece kit comes with one contact sensor, but chances are you've got more than one entry point in your home. And even if you started with the four contact sensors included in the 8-piece kit , sometimes you just need a few more. Add additional contact sensors and get real-time security alerts on your mobile device whenever a door or window opens at home. They mount easily to any door or window frame, and their tamper-resistant design and long battery life mean you can rest a little easier.