Original Xiaomi Smart Doorbell 4(Black)

1. Doorbell rated input: 5V/2A 2. Doorbell wireless connection: WiFi IEEE 802.11b/g/n/ax, 2.4GHz, Bluetooth Low Energy, 433MHz 3. Doorbell battery capacity: 5100mAh 4. Doorbell storage: Cloud storage 5. Doorbell operating temperature: -10°C to 45°C 6. Doorbell charging temperature: 0°C to 45°C 7. Doorbell compatible systems: Android 8 and iOS 12.0 and above 8. Doorbell receiver rated input: 100-240V, 50-60Hz, 0.04A 9. Doorbell receiver wireless connection: 433MHz 10. Doorbell receiver operating temperature: -10°C to 45°C 11. Doorbell receiver operating humidity: 10%-90% RH, non-condensing 12. Dual cameras, upper and lower, with a wide field of view 13. 3MP HD main camera captures crystal-clear details outside your door. 14. Infrared night vision provides clear visibility in dark corridors. 15. 120-day battery life eliminates the need for frequent charging. 16. Wide infrared sensor coverage accurately detects whats happening outside your door. 17. 72-hour free cloud storage for easy playback of important information. 18. Supports Xiaomi Pengpai Smart Link for cross-device access to door activity. 19. Security chip encryption protects data and privacy. 20. Voice-changing intercom function prevents gender and age from being revealed. 21. Two-way calling for easy access to doorbell status. 22. Multiple anti-lost features and removal alarm.