Ultrasonic waves of 125 decibels are very irritating to the dog's hearing. The longer you keep this posture, the more damage it will do to him, and he will run away quickly. Principle of dog repellent: The dog repellent is mainly used in outdoor environments to prevent dogs from attacking. When the dog tries to attack you, you can take out the dog trainer and emit ultrasonic lighting to the dog: switch on the button at the bottom of the gear selector to "Light", the button switch "ON" on the top of the product can be used as a flashlight.Dog training: Turn the gear selection switch at the bottom of the product to the "Train" button, and switch the button on the top of the product to "ON" to generate ultrasonic waves, and you can train the dog at this time.Prevent Attack: Touch the gear selection switch on the bottom of the product to the "Chaser" button, and the button on the top of the product switches "ON", the dog will run away.Simple operation: just put the dog repellent close to the animal, and hold it for 2-3 seconds, press the switch button, under the proper operation, only the animal will hear the ultrasonic sound, but the human will not hear the sound.Note: 1. In the dog repelling mode, due to the strong power and high power consumption, please do not press the switch for a long time, usually 3 to 5 seconds, then release the switch, and then press it again. 2. Do not use near the human ear. Product does not contain batteries.