1.Using a particular frequency ultrasonic wave to train dog and don't have any harmful to dog.
2.The ultrasonic waves is irritating to dogs, the high intensity sound waves are out of the hearing range of human beings, but able to be heard by dogs up to 50 feet away.
3.Also, can use the sonic to train a dog and improve its behavior.
4.Beautiful appearance, easy to use.
5.Can be use as a flashlight.