Review on KAiF Handheld Dog Repellent and Anti Barking Control Device - Powerful Ultrasonic Dog Bark Deterrent - Safe and Humane Bark Stopper and Dogs Repeller - Effective Behavior Pet Training Solution by Tiara Andrews

If you do a little research and look online for examples of usage, it really works. I have four dogs and one of them is very anxious and barks at everything. You have to give a verbal command when using it, you can't just use it because light is part of its work. If the dog does something you don't want, say "no" in a stern voice, then point the object at the dog and press the button. Then, when the dog stops behaving, give him praise. "No" gets the dog's attention and also creates a pattern in their mind that an uncomfortable light and sound follows "No," but when they stop, they receive praise and positive attention. After only a few times, my dog realized that "no barking" meant just that. Now when he hears a knock or any other strange noise, he looks at me and I just say "don't bark" and he stays silent. Then I praise him and he goes on with his day without me having to worry about barking. After a week or so I don't even need it anymore. Because the light and sound are aimed at him, the other dogs know they're not and ignore him completely. That's why it doesn't work in dog parks and places with a lot of dogs who don't know which dog you're talking to.