Battery in the wireless doorbell
Wireless doorbell for an apartment : Battery In The Wireless Doorbell
Quote from Article entitled Wireless doorbell for an apartment:
We should also mention an electric bell with a camera. It allows you to see who come to you in your absence. Pressing the button turns on automatically recording on a flash card or another date storage device. It should be installed where a good view on the zone in front of the entrance door will be provided. Devices with a camera can be relatively simple in design and equipped with additional functions and therefore more expensive.
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