Safe anti-barking device for dogs: the ultra dog trainer uses the principle of ultra waves to stimulate the dog, causing the dog to stop its current behavior. When the device is turned on, it emits a frequency between 10 kHz and 30 kHz, which is outside the range of human hearing but within the sensitive hearing range of dogs. The sound does not have a negative effect on the hearing or health of dogs. Effective for dogs of all sizes: the ultra anti-barking device features 3 adjustable frequency levels and is suitable for dogs aged 6 months to 8 years. Frequencies include 15-30 kHz for large and energetic dogs, 20 kHz for calm dogs, and 30 kHz for small dogs. It can effectively address various barking behaviors. Adjust the frequency as needed to maintain training results. Three adjustable modes: the device emits ultra sound to deter or train dogs. A flashlight mode can be used to capture the dog's attention. The LED light can operate in combination with the ultra wave to help stop barking. Some dogs may not respond immediately to the sound. Allow up to 2 weeks for effective training results. Portable design: this compact and portable ultra device is easy to carry during walks, jogs, or runs. With an effective range of up to 25 feet, it is ideal for training dogs both indoors and outdoors. It can also help keep other dogs at a distance during outdoor activities.