[Window & Door Alarm Sensor for Home Security] SwitchBot Contact Sensor can detect the opening/closing of doors and windows, guarding security of the elderly, children, and pets. With the built-in light sensor, it will automatically trigger the Switchbot Bot to turn on the light when someone moves when the environment goes dark. The magnets need to be aligned with the bottom of the body, and the distance between the two components needs to be less than 1.2 inches (30mm).

【Perfect fit for all windows】Easily adjust the retractable curtain box for a snug fit, even with measurement errors. Covers window widths from 43.3' to 55.1'(Check Size before puchase).

Update your curtains effortlessly, no modifications or tools needed. Hang the curtain 3, install the positioning magnets and connect it to our app. Three easy steps for smart curtains in any room. Suitable for bedrooms, living rooms, offices, children's rooms and more.

Motion & Presence Detection: Presence Sensor combines mmWave radar with light-sensing technology and PIR sensor to accurately detect subtle chest movements from stationary humans. Perfect for bathrooms, reading, or office use, it prevents lights from turning off unexpectedly and enables automated lighting.

Battery Design & Flexible Installation: Equipped with a long-lasting battery, this sensor frees you from power cables and can operate up to 2 years on a single charge. The magnetic base allows flat placement, wall mounting, and adjustable detection angles, making it ideal for bathrooms, living rooms, studies, and other areas throughout your home.

Smart Home Ready: Seamlessly integrates with Alexa, Google Assistant, Siri, SmartThings, and Home Assistant via Bluetooth. Enjoy hands-free control and effortless automation in your smart home. Additionally, pair with the SwitchBot Remote (local Bluetooth connection) to conveniently control your curtains' open and close functionality with a simple button press.