This ultrasonic dog training device combines training functionality with bark control. The device can effectively train dogs to be obedient and stop unwanted behaviors such as barking, digging, improper eating and more. The device will help repress and deter constant barking, allowing you to finally relax and work in peace. Comes with an anti-static wrist strap, helping keep the device securely on your wrist. Includes an indicator that emits a green LED light when working. Powered by 4 AAA Alkaline batteries. This device has a control range of 16.4 ft which makes it ideal for outdoor and indoor use. The device detects dog barking through a sensitive microphone. Just a push of the button emits an unpleasant ultrasonic sound which can only be heard by your dog. The dog will learn to associate the noise with the bad behavior. Press and hold the switch button to activate, after 10 seconds the noise will automatically turn off. 100% SAFE: The average human hearing frequency range is 20HZ~20KHZ, with dogs hearing a wider range from 15HZ to 120KHZ. This device emits ultrasonic sound at 25KHZ which cannot be heard by humans, but can be heard by dogs. A much safer yet effective alternative than other forms of bark control. Ergonomic design makes it easy to hold and control. The ultrasonic dog training device fits your palm nicely. Small and compact allowing for easy carrying.