18V Compatible with: Ring Video Doorbell，Ring Video Doorbell 2，Ring Video Doorbell Pro，Zmodo Smart Greet Wi-Fi Video Doorbell,Nest Hello Video Doorbell. Necessary for your Doorbell: It's the most simple and convenient way to operate your Video Doorbell,with the Power Adapter,you can let your Video Doorbell continuously running and no need to remove your doorbell for charging the battery.
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