Know the Status Stop wondering if you closed all your windows after leaving home. Check on your doors and windows at a glance with the Tapo app. Turn Lights On Automatically Set your Smart Contact Sensor to trigger on the lights when you open your door. Go Beyond Just Doors and Windows Place the Smart Contact Sensor elsewhere like your cabinets and drawers for more convenience. Instant Push Notifications Receive instant alerts on your phone when a door or window is opened unexpectedly. The Hub can sound a siren to warn of danger and deter intruders. Long-Lasting Performance 1+year battery life provides long-lasting convenience. * Receive notifications from the Tapo app when the batteries are low and need changing. Easy Installation Place it wherever you need with our tool-less installation. The gap between the sensor and magnet (up to 15 mm) fits most doors, windows, and other fixtures. All in One App Experience your next-level smart home with the Tapo line all in a single app. Create a more secure, convenient, and comfortable living space for you and your loved ones.