Feature: 1. Message push setting. When the emergency button is pressed, it is transmitted to the cloud through the gateway(not included), and then the message is pushed to the mobile APP. 2. Linkage control. When the emergency button is pressed, the added lights and curtains, etc, are turned on or off according to the first set method. 3. Low battery alarm. When the battery is too low, automatically push a message to the APP. Record for the record. Real‑time record the use of the alarm, save 7 days of historical records (automatic coverage). 4. For Tuya Zigbee smart smoke alarm can be remotely controlled by a mobile phone and can be connected to other for Tuya‑supporting products in the home. It must be used together with the zigbee 3.0 gateway (not included). 5. It has a wide range of applications and is widely used in homes, hotels, hospitals, nursing homes and other places that need it. Specification: Item Type: SOS Button Material: ABS Size: Approx. 52 x 17.3mm/2.0 x 0.7in Operating Voltage: DC 3V Wireless Type: ZigBee Alarm Current: ≤ 25mA Static Current: ≤ 5mA Power Supply: 1 x CR2032 button battery, 100mAh (built-in battery) Battery Life: More than 1 year Low \Voltage Alarm: 2.5V ± 0.2V Communication Distance: More than approx. 50m/54.7yd in the open space Operating Temperature: -10℃ - 50℃. Package List: 1 x SOS Button1 x Lanyard1 x Manual