OVERVIEW: Make sure the doors and windows are shut. Ring Alarm Contact Sensors easily mount to any door or window frame in your home for easy, DIY installation. With real-time alerts from the Ring App when your Sensors separate, you’ll always be the first to know when something’s ajar. Plus, if you’ve enrolled in our optional Alarm Professional Monitoring1, you can choose to receive a call from the monitoring center when the Contact Sensor is triggered and request emergency assistance if...