KIVORA 4 Pack Dog Whistle to Stop Barking Neighbors Dog,304 Stainless Steel Adjustable Ultrasonic Silent Dog Training Whistle for Recall & Bark Control,Professional Whistle Suitable for All Dogs

The dog whistle operates within a high-frequency sound range, including ultrasonic frequencies above 20kHz.

The human hearing range is approximately 20Hz–20kHz, while dogs can hear frequencies up to approximately 60kHz. When the whistle is adjusted above 20kHz, the sound becomes inaudible to humans but remains effective for dogs.