Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Viatek Bark-Stop a waste of $

I purchased this device because my neighbor's dog barks whenever we are outside. I spoke to them about the dog, but there is little they can do about it themselves. The problem with the bark-stop is that it will not go off when the dog barks! It is only ~20 feet away and the dog barks very loud (big dog), but the thing only goes off when I move or bump it. I tried all settings etc and no luck. I don't recommend you buy this device and would hope there is something more effective on the market.