Doorbell supports class 10 micro SD card from 8G to 128G. Please format the micro SD card(included) before use. Place the new battery in the battery compartment with the correct polarity. Doorbell currently supports 2.4 GHz Wi-Fi network only ( 5G is not supported). Instant Notifications When someone presses the doorbell or any motion is detected, you can receive instant notifications via app so that you will never miss your visitors. Home Security Protection With Victure video doorbell camera, you can know what happened before your door anytime, anywhere.Protect your family from being disturbed all the time. History Alarm Record You can easily view the alarm messages arranged in chronological order in the APP, and you can clearly know when the visitor came.