Specifications:

• Upgraded version: Ultrasonic anti-bark device automatically detects barking from 15m / 50 feet away. A bark control device that emits a high-pitched sound that only dogs can hear. When your dog stops barking, the ultrasonic bark control will automatically stop emitting ultrasound waves.
• SAFE FOR DOGS AND PEOPLE: Ultrasonic frequencies are harmless to pets and completely inaudible to human ears, so you can safely use this device. Widely used to prevent your dog or your neighbor's dog from barking.
• How to use: Hang it on a tree, indoor or outdoor wall or fence post to stop your dog from barking (within range). The premium outdoor ultrasonic barking alarm clock detects excessive barking and the microphone responds by barking and parts activation.
• Design: Requires 9V battery (batteries not included). The outdoor ultrasonic barking device has a power indicator. When you leave it, you can set it to "off" to protect the battery. This is an outdoor ultrasonic barker designed for outdoor use.

3 Level Sonic Bark Deterrent Dog Bark Deterrent Device, 50 Feet Indoor Outdoor Dog Bark Deterrent Tool for Dogs 6 Months to 8 Years Old