- Brand: Ring - Model: Video Doorbell 4 - Power: AC 12V-24V I believe the battery is usable. However, the main unit's recognition keeps getting interrupted no matter how many times I try. Therefore, I am selling it as junk. Acquisition history: Yahoo! Auctions Initially, the activation was not cut off, and after waiting for a few weeks after contacting Ring, I tried to reconnect. However, it still doesn't proceed from the middle. It reads the QR code, but the connection to the doorbell is cut off around the white blinking stage. Therefore, the doorbell unit is considered junk.