Function: Our dog barking silencer is used to prevent excessive dog barking, calming anxious pets, and training puppies. No more neighbor complaints with our anti barking device outdoor Auto Dog Barking Control Devices: Automatically sense the dog"s sound, once the dog stops barking, Our ultrasonic dog barking control will automatically stop emitting ultrasonic waves Powerful: With New Tech, The effective range of ultrasonic penetration is 50ft area, and with 4 Adjustable Modes(test, low, medium, and high), makes the bark control more flexible than other anti barking device Safe for Dogs & Humans: This dog bark control using high-frequency sound to discourage barking, easily and discreetly control unwanted barking and even ward off wild animals Indoor and outdoor: Our dog silencer made by ABS plastic, waterproof and durable. The bark control pro is perfect for stopping dogs from barking both indoor and outdoor environments