Dog Whistle to Stop Barking - Silent to Humans but Effective on Dogs - Better Than Electronic App - Great to Silence Train or Repel A Dog's hearing goes further into the ultrasonic range than people's so they can hear these whistles. In other words, it is very LOUD to dogs but very QUIET to people. A dog whistle is a great tool to use in dog training but equally as valuable with dog communicating. It is especially helpful in louder, social situations when you want to get your dog's attention without bother others around you You can use a dog whistle to stop barking; however, it will only be a temporary relief. Don't be fooled by others who claim that their dog whistle will stop their dog from barking. It may work momentarily because but it is just a brief distraction to the dog and they most likely will continue barking. You can use this whistle as part as a basic skills training for your dog which is more likely to achieve the desired results Silent dog whistle works just like any other whistles -- you blow through them and they make a noise. It is called a "silent whistle" because it operates on a frequency above that of the average person's hearing. You will hear something, but not much. This is expected because you want your dog to hear it and respond to it This is great to use in conjunction with a dog whistle app which can be downloaded for free. You don't need to invest in more expensive electronic dog whistle or dog whistle repellant that have not been proven to achieve any better results. Here's a hint, the harder you blow, the more sound you will here and the less sound your dog hears We never make promises we can't keep and we prove it with our 100%, No Questions Asked Total Satisfaction Guarantee. If you don't find that your dog will grow alert and responsive to your whistles, simply return for a prompt refund of the purchase price. That's our Guarantee!