New Anti Barking DeviceThis dog barking device safely and gently emits sound waves, preventing dogs from barking without causing any physical harm to dogs. We recommend that as long as the dog reacts to the sound of the equipment and calms down, it is important to praise and reward the dog for its training in time. Continuous training is a necessary condition to achieve effective and lasting results.Four powerful ultrasonic transmitters stop barkingThe anti barking device for dogs is equipped with four powerful and effective ultrasonic speakers. This dog stop barking device can prevent dogs from barking more effectively than traditional single-speaker devices. The acoustic bark control device works effectively in a maximum range of 33 feet.3 Frequency ModesThe canine bark deterrent applies to dogs of different sizes or breeds. 1. Audio mode, which outputs a variable frequency of 10 - 16 khz, suitable for small or sensitive dogs. 2. First-class acoustic mode, emitting 20khz, suitable for docile or medium-sized dogs. 3. Second class acoustic mode, with 25KHz emission, suitable for naughty or large dogs. The ultrasound frequency is harmless to pets and humans.Rechargeable & IP45 WaterproofThe barking equipment can be fully charged in 5 hours, and the equipment can work continuously for up to 30 days. The dog stop barking tools are small and lightweight, and you can take it anywhere, such as hanging it on a tree, wall or fence, to prevent your cute dog or a neighbor"s dog from barking. Make sure the bark controller is facing the dog within the effective range and there are no obstacles.Satisfactory Customer ServiceApplies to most dogs, but not to deaf and dumb dogs and hearing-impaired dogs. Each dog"s behavior and tolerance is unique, and each dog"s response to different degrees and methods of correction is also different. Allow two weeks to use the device to train your dog.