The SimpliSafe ES3 (4 Pack) Entry Door Window Sensor in white is a brand new third generation product. It is designed for indoor use and offers wireless connectivity through Bluetooth and Wi-Fi. These door sensors are compatible with SimpliSafe systems and provide an added layer of security to your home by detecting when doors or windows are opened or closed. With a sleek design and easy installation, the SimpliSafe ES3 sensors are a practical and reliable choice for home surveillance.