A built in microphone senses constant barking and triggers an ultrasonic tone inaudible to humans, to help cure problem behavoir.
Using effective ultrasonic sound, the PetSafe® Outdoor Bark Control Birdhouse cues dogs to stop annoying barking. Effective to fifty feet; has three Sensitivity Levels.
Viatek’s Professional Bark Stop lets you choose from two different frequencies: Ultrasonic frequencies and Sonic Frequency. In Ultrasonic frequency it can only be heard by dogs, not humans.
Produces a discomforting but not harmful high frequency sound that can be heard only by your dog or cat.