VANZO Ultrasonic Dog Bark Deterrent, Dog Barking Control Devices with 50 FT Range, Anti Barking Device for Indoor & Outdoor, Black-

My next door neighbor had an untrained labador who constantly barked to let in when it was outside, and the owner never trained it to be quiet. I hung this on the corner of my house. The mounted height is 5 ft, location is 5 ft to the 6 ft tall fence, and the fence is about 20 ft to the back door of neighbor where the dog stayed. The dog just barked once and it stopped. It still barked some time, but it stopped after one low tone bark. So apparently the ultra sound worked. One month later: This device worked if the dog was directly in sight, it was no good if the dog was farther away in the yard, or it might have accustomed to the sound. So the sound was not powerful enough. Latest: Total failure, battery lasted less than one week. Wasted money.

We bought this because we have a neighbor's dog that barks non-stop. We were desperate! The birdhouse is so easy to set up, our 13-year-old did it in less than 5 minutes. At first, we put it on the 15 ft. and that did not seem to be enough. We upped it to 30 ft. and we finally have peace and quiet. It works immediately and the barking is gone. I only wonder what the neighbors are thinking, if they have noticed how quiet their dog finally is, ha! What a great purchase this was.

Does not work for our dogs. They didn’t even seem to notice

These work for really well with dogs who have normal nerve strength. Deaf or aggressive dogs are only slightly affected by this. It has helped with our mini schnauzer. Quality was as expected and it arrived quickly. My mom also uses in her back yard for neighbors dogs who bark non stop.

Not at all effective on chihuahuas, pit bull, malinois, or aussies belonging to neighbors. If anything, it set them off to bark more.

This really helped my dog stop barking inside took about 2 weeks to be fully effective but really helped

I followed the instructions. Placed them at the right height, facing the right direction, and within the right distance...even got 2 so there would be extra coverage. They were effective for all of about 12 hours. My neighbors have 4 dogs that live outside and constantly bark. 11am, 3pm, 11pm, 3am...it doesn't matter. They make noise. A lot of it. One of them is loud enough that I can hear her squeak-toy-sounding-bark across a 1/4 acre yard, through double sliding glass doors on the opposite side of my house. When I put these up, my dogs (who already don't bark unless there's a new/unwanted person around) immediately ran from the noise being triggered. The dogs next door would start to bark and immediately stop and stare in the direction these were placed, then wander off quietly. Great, I thought, they were working. This continued through the next morning. Short bark, stop, stare, wander off. By the next afternoon though, it was like they had become immune to it, or they figured out if they all four get going loud enough they can drown it out maybe? I don't know. Either way, it isn't effective enough and was a waste of money - both for the units themselves and the additional bulk batteries I bought.

I guess it works for some dogs. Not mine!!!