Safety and humanityThe anti-barking device uses ultrasonic technology, which uses physical methods to stimulate the dog to bark and effectively prevent unnecessary barking. The ultrasonic barking deterrent is also a safe and effective training tool, and will not cause any harm to the dog's body. Upgraded Adjustable Ultrasonic Level ControlSuitable for small medium large dogs! Emits harmless and effective sound to control excessive barking, but some dogs may be afraid or dislike the sonic sound, not stop barking at the beginning, so please allow up to 2 weeks for training. Unique Birdhouse DesignThe designer chose ABS plastic from a variety of materials, which is very shattering resistant. The interior is also installed with fixed devices, and lightweight, super cute design, suitable for outdoor decoration. Durable &WeatherproofUltrasonic anti-smashing, durable, weatherproof, sturdy bark box bark control, lightweight, waterproof material, can withstand any weather conditions .Excellent outdoor barking control!