Usage Tips: Automatic Dog Bark Stopper: The device intelligently captures dog barking from up to 50 feet away, and automatically emits an ultrasonic sound that distracts your dog to stop unwanted barking, allowing you to to enjoy a moment of peace and silence. Dog Barking Stopper: Ultrasonic frequencies are harmless to pets and completely inaudible to the human ear . If the dog is hard of hearing or aggressive, the device may not work as expected. It is not recommended to use one device against two or more dogs barking at the same time. 3 Levels of Operation: The adjustable frequency dog barking deterrent device is suitable for different dogs. 15KHZ-30KHZ is suitable for big vicious dogs. 20KHZ Suitable for gentle dogs. 30KHZ Suitable for small dogs. It is recommended for dogs aged 6 months to 8 years old. USB Rechargeable: The ultrasonic dog repellent built-in a rechargeable lithium battery, the device can work continuously for 30 days after fully charged in 5 hours. Red/blue color indicates battery status. Easy Installation And Waterproof: The dog bark stopper can be hung on a tree, wall or fence to prevent your own dog or that of your neighbors barking. Make sure the bark controller is facing the dog within easy reach without any obstructions. The ULTPEAK Ultrasonic Bark Control Device is the most humane and effective way to bark control. stop unwanted barking, friendlier and safer than electric dog collar. Operation Instruction - Power on: set the button to level 1, level 2 or level 3. Blue light flashing means the device has been powered on. - Standby: Blue light flashes every 6 seconds. - Starts working: Red light stays on for 3 seconds. - Low power: Red light starts flashing. This means the device needs to be charged or it will stop working. Keep in mind - The maximum detection range is 10 meters, the bark stopper will not be triggered by the barking of the dog if it is out of this range. p> - The anti-bark device will not work for hearing impaired or aggressive dogs. - It is recommended for dogs 6 months to 8 years old. < p>- It is not recommended to use one device against two or more barking dogs at once. - Make sure the bark controller is turned to the dog within range without obstruction. - It is not recommended to use the same ultrasound frequency on the same dog for 10 days or more. The dog may have resistance at the same frequency. Please change the frequency every 7-10 days. Package Included - 1 x Bark Control Device - 1 x USB Charging Cable - 2 x Mounting Screws and Anchors - 1 x User Manual Sold by the store