Ultrasonic Pest Repeller: Ultrasonic waves can stimulate the brain and auditory nervous system of pests to keep your home safe from all kinds of pests Two light modes: the light can be chosen - on and off, it is more effective to turn on the light, the light can also act as a small night light Wide Coverage: Its ultrasonic wave can cover an area of 80 to 120 square meters. Since ultrasonic waves cannot penetrate walls and solid objects, it is recommended to put one in each room