Power Supply: 110/220V AC Backup Battery: 3.7V, 300mAh Lithium Battery (included) Consumption: Radio Frequency: 433MHz Wi-Fi: IEEE 802.11b/g/n App: Compatible with Tuya Selectable Melodies: 58 Volume Levels: 5 (includes mute) Sound Level: 85dBA (typical) Expandable: Supports up to 100 doorbell buttons/sensors and 10 remote tags Operating Temperature: -10��C to 55��C **Doorbell Button Specifications:** Power Supply: DC 3V (1x CR2032 Lithium Battery included) Standby Current: Transmitting Distance: 100m/328ft (open space, no interference) Radio Frequency: 433MHz Size: 68x43x17mm / 2.7x1.7x0.7in Operating Temperature: -10��C to 55��C **Features:** - Wireless Wi-Fi doorbell with SOS function. Supports 433MHz devices for home security. - Includes alarm clock function with remote scheduling via app. View alarm history anytime. - Suitable for homes, offices, or care facilities. 58 melodies to identify triggers. - Pair up to 100 wireless devices (328ft range in open space). - Low battery alerts for connected accessories via app. - Share alerts with family/friends through the app at no extra cost. - Manage multiple doorbells via the app. **Package Includes:** - Doorbell x1 - 3M adhesive x1 - User manual x1