The Perfect Training Tool: Anti-barking device the ultrasonic wave of the flashing flashlight is effective on dogs and can painlessly change all annoying, unsafe behaviors under full control in 3 seconds,in Deterrent mode, it will emit a powerful ultrasonic wave while flashing the flashlight,suitable for indoor and outdoor use. Hearing Sensitivity: ~3% of dogs( 50pounds) do not respond to the device,we refuse to stop short of 100% effectiveness. The average human hearing range is between 20Hz and 20KHz, while dogs have even more hearing, to perceive sounds in the range of 15Hz to 50KHz. Our ultrasonic barking controller emits ultrasound at 25-30KHz, which is a frequency that is highly coordinated with your dog. User-friendly: Our barking deterrent includes a flashlight mode for walking dogs at night.Its design characteristics are bright at night, clear lighting, not afraid of the night, there are buttons. USB Charging: The ultrasonic barking control uses a new USB charging instead of the traditional battery device.2 hours of fast charging, working for about 60 days, no need to worry about running out of power, charging anytime and anywhere. User-friendly Design: Ultrasonic barking training device that completely frees your dog from cruel shock collars. Make your neighbors more harmonious, sleep quieter and live a Colour:Yellow Material:plastic Package Contents: 1 x Ultrasonic Dog Repeller 1 x USB Cable 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.