My dog Luci ( a Border Collie/Lab mix) will bark at her own shadow. She barks when the doorbell rings on the television. I have 4 other dogs and she would get them all going. One of my dogs has diabetes and is blind but just because the other 4 were barking she would also chime in. I put the collar on Luci since she is the instigator. The first time the door bell rang on TV , she started to bark . Gave her a couple of warnings and then much to her surprise it gave her a little static vibration. I had it on the lowest setting and it did her no harm. I could not be happier. It only took her one time to realize if she barked she was going to get a little static vibration.. Now when she gets the urge to bark she lets out little woofs and then decides she better not do it. No more yelling at them to stop the barking…nothings there. I could not be happier with the peace and quite. I wish I got this sooner.( like six years ago ) She only wore it for a couple of days and got the message. I now am going to pass it down to her sister that she has taught her bad habit. I received this product for a discounted price. All my reviews are based on my own experience and evaluation of the product so that others can benefit in finding quality products that meet their needs & expectations.