2PCS Ultrasonic Mosquito Repeller, Ultrasonic Mosquito Repeller Electronic Ultrasonic Pest Repeller Ultrasonic Insect Repellent (European Standard) Ultrasonic Insect Repellent kill mosquitoes etc. in your room. cockroaches, mice, moths and other insects. Safe: Ultrasonic Rodent Insect Repellent People and pets can’t hear the sound. No harm to human and pet health. Easy to use: This machine should be installed 80-120 centimeters from the ground. And vertical to the ground and plug into the power outlet. Wide Coverage Area: This pesticide can be used anywhere in the house, such as the kitchen, bedroom, basement, garage, warehouse, etc. Ultrasound devices cannot pass through the wall, installation a control device for one or more separators necessary for a large room.