Very good choice. It does what it says. It has a motion sensor and when the bird approaches, it emits a loud sound like a predator. The problem arises with the neighbors, who after a few days start complaining about the annoying sound.....

Just a few hours ago I received it...
Initial negative point is that in order to adjust the sound, volume, and time, you have to unscrew the lid where the batteries go...
The sound is quite loud, time will tell if it will be effective...

I saw it installed in a health store. I bought it and it has been working for 1 week with batteries. At the same time, the area was disinfected and nests with eggs were moved out of the area in combination with the machine (which withstands extreme weather conditions very well). There were about 10-12 persistent pigeons and we spotted one after a week within a 2-hour period and at a distance of 50 meters.

If the above actions are combined and there is patience for a few weeks, the problem is minimized and maybe even solved.

A very good purchase.