Features: 1. Smart SOS Sensor: A Wireless Gateway Hub is a must to work with the SOS sensor, as well as a variety of smart products, which is proved to be the bridge and control center for smart homes and plays an irreplaceable role for all products and realizes the whole intelligent linkage of your house. Simply add the sensor into the hub after adding the hub into Smart Life App.  2. One click alarm for emergency help and Smart Life App compatible for smart phones push notifications by receiving the alarm information from the sensor on smart phones anywhere, anytime needed.  3. Wide applications with its mini design and fits for the elderly and children particularly by pressing it gently to send the emergency help. No complex operations and buttons.  4. DIY compatible control: DIY supported for the sensor to smart linkage to other smart devices, detecting opening/closing, movement, water, fire and more smart scenes.  5.100dBm emission frequency and battery powered; carry it anywhere you like with the rope, use with the gateway hub to define the working mode of the scenario anywhere from anytime.     Specifications： Name: SOS Emergency Button Sensor;  Material: ABS;  Wireless frequency: 2.4GHz;  Color: White;  Emission frequency: 10dBm;  Emission current: Peak value 45mA, average1～2mA;  Quiescent current: 2～3uA;  Emission distance: 100m+(Open space);  Battery: CR2032;  Working temperature: -20℃-60℃;  Working humidity: ≤95%RH (non-condensing);    Package included: 1 x SOS Emergency Button Sensor;  1 x User Manual;  1 x Needle