Too early to tell
I heard *something* in my basement drop ceiling and I freaked out so I went and got 10 of these as well as a dozen mouse traps. So far, my basement has been quiet and all the mouse traps are empty. I did find mouse droppings in the ceiling though. I will come back and update this review if anything changes.<br />The good thing about these ultrasonic devices is that you simply plug it in the wall. You also have an on/off button on them so you can temporarily disable them.<br />The bad thing is that you never know how effective they are. I also read online that pests tend to "get used" to the the sound and eventually they learn the sound pose no danger to them so they start ignoring it.
Rating: 2 stars