Ultrasonic Dog Trainer Using the latest ultrasonic technology, Wango Barking Trainer is suitable for dogs of different breeds and sizes. Ultrasound frequency is harmless to pets and humans. It can be used as a dog repellent and dog training aid to stop bad dog behaviors such as endless barking, searching and fighting. [Portable anti-bark design] This device The dog bark control device is lightweight, very suitable for putting in a pocket, and suitable for indoor and outdoor use. Equipped with a wrist strap, easy to carry. Press the button of this bark control device, it will emit ultrasonic waves, at the same time, the green light indicates the device is working and the red light indicates the device needs to be charged.[Rechargeable Dog Bark Controller] Our new version of the ultrasonic dog bark controller makes training your dog easier. Comes with a USB cable, the anti-bark plug can be fully charged in 5 hours and can work continuously for 15 days. Compared with other similar products that require batteries, our products are more environmentally friendly and save money. [Effective dog barking deterrent] The control range of our bark control device can reach 16.4 feet and it emits ultrasonic waves at 24 kHz. This sound will not affect humans (the hearing limit is 20 kHz). With beeps and ultrasound, it can easily attract the dog's attention and improve bad behavior. Continuous training is necessary to achieve effective and lasting results.