The hearing range of the human ear is about 16-20000Hz. The output frequency of the ultrasonic mouse repeller is generally above 20000Hz. The human auditory system cannot respond to the frequency above 20000Hz, so our ears cannot hear it at all, and the power of the ultrasonic mouse repellent has not reached the ability to penetrate the human body, so it has no effect on the human body. For cats, dogs and other pets, as long as the output frequency of the mouse or insect repeller is not set in the sensitive area of the cat and dog, it will not cause any impact. Our pest repellers are no toxic sprays, chemicals or poisons. Using Ultrasonic technology that is 100% safe for the environment, people, pets and children.