The Ultrasonic Dog Bark Control Device is an effective training tool and barking deterrent. It can prevent dogs from barking and correct unwanted behavior such as jumping up, digging, chasing, trash raiding, and excessive barking. The device emits an ultrasonic sound that can only be heard by the dog, with a frequency of 25KHZ and an effective range of 5 meters. The sound is high-pitched and irksome to dogs, while being soundless to humans. It is easy to use, with just a push of a button. The device is small, lightweight, and fits perfectly in your pocket, making it convenient to carry around. It is suitable for indoor use and walking the dog outdoors. Made with high-performance ABS material, it is also waterproof. The LED light on top indicates working status and low power mode. The ultrasonic dog bark deterrent is suitable for all size dogs, from small to large, and can be used on dogs from 6 months to 8 years old. It has 2 different levels and the ultrasonic frequency can be adjusted according to the dog's condition. We recommend starting with low power and increasing as needed. Please note that the device may not be effective on hearing-impaired and old dogs. It is recommended for use on dogs above 5lbs and should not be used on aggressive dogs.