SAFE FOR DOGS AND HUMANS: The ultrasonic barking control device is the perfect dog training and dog barking control device. This dog bark silencer emits ultrasonic waves with a frequency of 22KHz to 27KHz, which is very sensitive to dogs and has no harm to dogs and humans. Suitable for small, medium and large dogs, without any harm to the dog. Anti-Bark Device with 3 Modes: This ultrasonic dog bark deterrent stops barking and trains your dog with three wave patterns: steady and continuous frequency, regular frequency, irregular frequency. Multiple ultrasonic modes can be adjusted according to different situations. Rechargeable with LED SOS: The barking control device can be charged with a Type-C cable, fully charged within 2-3 hours, and lasts up to 60 days. LED flashlight and emergency SOS function make it safer and more convenient for you to walk your dog at night. Slimner and Compact Bark Deterrent: The Ultrasonic Bark Deterrent comes in a slimmer handheld shape. It makes it very convenient for you to put it in your pocket or hold it in your hand, easily take it anywhere you want, stop your dog from barking and train your dog indoor/outdoor. Stop Neighbors' Dogs From Barking: The 25-foot range control helps stop other dogs from approaching you while jogging, walking, or biking. You can also use it to train your dog to stop behaviors like digging, fighting, chewing furniture, eating unsafe food and other bad behaviors. The best dog training tool.