I've spent a year in my hallway, still fine. Perfect for our needs as my cat is getting old and wants to turn on the hall light but leaving my door open for him makes me worry when trying to sleep (not to mention leaving the light on all the time ). Thing). I've noticed that my daughter can call it from afar, but it works on a cat, which was its intended purpose. By the second day I thought it wouldn't work anymore, but there was just enough natural light falling on it and it didn't work. Nice too, but it surprised me since the hallway is usually dark.