I bought this door entry camera in the mistaken belief that the monitor screen was separate and detached from the camera.
I assumed that the doorway could be monitored without having to go to the door!
It turned out that the screen is connected directly to the camera via a hole you have to cut in the door.
I can't see the point of having an expensive electronic device like this when an ordinary glass version would do the same job, for a fraction of the cost.
As I said, pointless AND a waste of money.
I returned it, unused, but the seller held back £13, I have no idea why, I did ask, but they ignored me. I paid the return carriage of £6, so I lost almost £20.