Deterrent Device has 3 adjustable levels. Different dogs may be sensitive to ultrasound in different frequency bands. Please turn the knob to test different frequency bands for best results. If you or your neighbor's dog barks too excitedly, put it in the right spot, and you'll have a quiet resting environment. [Easy to Use]Anti barking device has a built-in pickup that can detect the dog's barking within 50 feet and automatically emits ultrasonic that the dog can hear. Once the dog stops barking, the device automatically stops. Compared with the traditional dog training device, it completely frees your hands. Automatic and effective training your dog to stop excessive and noisy barking. [Energy Saving]Operates 9-Volt batteries (not included), average battery life 5-6 months depending on use. It can be started with a 9V battery (not included). Turn the knob to the "Test" button, keep it at arm length and whistle into the microphone, the device beep and the LED flash green ready for use. If you have any questions, please contact us. [ & Waterproof Barking Box]Dog barking has IPX4 waterproof, the case is UV and not easy to fade, professional design allows you to use the anti-bark device without worrying about the weather. And it is designed to be easy to hang/installed on trees, walls or fence post to stop any dog barking (within range), indoor, outdoor and anywhere else. The dog deterrent device is not suitable for aggressive dogs and hearing impaired dogs. Colour:As Shown Material:ABS Package Contents: 1 x anti barking devices Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.