Battery Smoke Alarm: The smoke detector is built with an energy efficient and eco-friendly lithium battery with low power consumption, enabling an incredible lifetime of 10 years with maximum reliability; spares you the hassle of frequent battery changesand provides uninterrupted 24/7 protection, even during power outages Sensitive & Accurate: Built with an advanced photoelectric sensor and intelligent ST chipset, the alarm can quickly and accurately detect dangerous smoke levels from smoldering fires, and provide the earliest possible warning of fires; the dust-proofisolating plate inside the alarm ensures the detection sensitivity Smart Auto-Check: This year battery smoke detector has manifold self-inspection parameters with clear notifications; if it malfunctions, or if the battery is low, you will be notified immediately so that you can identify and resolve the problem quicklyfor comprehensive protection Easy Installation: The smoke alarm takes advantage of simple, stable, and wireless installation with the provided screws