Bark Control and Dog Training - The ultrasonic dog bark control device is an excellent device for dog training and dog bark control. The set ultrasonic frequency (24 KHZ) has a certain effect on dogs and helps you correct their behavior. Safe and Effective - The average human hearing frequency range is 20 Hz to 20 kHz, and the dog can hear a wider range of 15 Hz to 120 kHz. The ultrasonic bark control emits an ultrasonic sound at 24 KHZ, so the sound does not affect humans, but can attract the attention of dogs. For Indoor and Outdoor Use - This anti-barking device has an effective control range of 5 meters. You can use it to train your own dog or you can carry it to chase away hostile dogs you encounter on the road. Perfect for indoor and outdoor use. Suitable for dogs of all sizes - The anti-barking device is an innovative solution for dog barking and correcting unwanted behaviors. The ultrasonic dog training device is safe and effective for all types and sizes of dogs (5 to 120 lbs). Suitable for dogs from 6 months to 8 years old. Easy to use - When you press and hold the button of the ultrasonic bark control devices, it emits an ultrasonic sound that can only be heard by dogs, release the button to stop. No more complex operations are required. Delivery quantity: 1 set (host, manual, USB charging cable, lanyard) Color: Blackluckymeet