Introducing the Ring Alarm Contact Window and Door Sensor, 2nd Generation. This innovative indoor sensor keeps your home secure by sending instant mobile notifications whenever doors or windows are opened. Enjoy hassle-free setup with no tools needed, making it perfect for any homeowner. Each sensor comes equipped with two long-lasting 3V CR2032 batteries, ensuring reliable performance. Enhance your home security effortlessly and stay connected to your space. Don't wait—secure your home today with the Ring Alarm Contact Sensor!