Does your dog keep barking when see someone visiting which annoys you so much? Take this ultrasonic anti-barking device home and train your dog instantly! This dog bark control deice features 3 adjustable ultrasonic frequency levels, which emit sounds that dogs can hear but will not hurt them, efficiently stopping your dog’s barking. Equipped with long-lasting battery, this sonic bark deterrent can keep standby 60 days after fully charged about 6 hours. Suitable for dogs from 6 months old to 8 years old. The device can be mounted at garden fence, home, dog house, tree etc..