This product adopts the principle of infrared detection. When detecting animals, it emits ultrasonic waves and powerful LED flashes to scare animals away. It protects your yard, garden and more by helping keep you away from animals. This product simply drives away animals, does not contain any chemicals, and will not cause any harm to the human body. Product Description 1. There are 2 working buttons that can be adjusted: “Sensitivity” button (right): The sensitivity of the product can be adjusted, and the animal repellency is more targeted. Turn the knob clockwise and the detection range will increase. “Frequency” (left): Used to set the control frequency. Turn the knob clockwise and the frequency will increase 2. The ‘Frequency’ button works as follows: 0: disabled 1: 13KHZ-20KHZ can drive away mice, rats, minks and other animals 2: 18KHZ- 25KHZ can drive cats, dogs, foxes and other animals 3: 23KHZ-35KHZ can drive deer, birds, monkeys and other animals 4: Powerful LED flash can