Description Smart Technology: This ultrasonic mouse repeller emits ultrasonic waves of different frequencies (20kHz-45kHz) to stimulate the nervous system of insects and mice , making them uncomfortable and gradually running away. Intermittent changes in ultrasonic frequency prevent them from developing immunity and adaptation. Great Coverage: Each ultrasonic repeller covers an area of up to up to 80-120 square meters. It is recommended to install this hammer vertically 20-80cm above the ground. For best results, equip each room with insect repellent. Safe and environmentally friendly mosquito control: non-toxic, product-free chemicals, no radiation, low power consumption, no noise, 100% safe for humans and pets, you will say goodbye to mousetraps, mosquitoes, mousepads, harmful poisons, and insecticides Etc, do not have batteries will save you a lot of money and give you a 100% safe and eco-friendly home. Super Quiet and Effective Mosquito Repellent: Ultrasonic Mosquito Repeller uses low frequency ultrasonic waves, so it allows you to control pests silently without disturbing you and your pets. Note that this requires a process. Depending on the environment, the response time is different, usually 2-6 weeks, we sincerely help you keep pests away. Easy to use: /em just plug the repellent into an outlet and it will work. Insect repellents immediately repel pests without killing them. No batteries are needed, saving you a lot of replacement work. Packing List:Ultrasonic Repeller Against mosquitoes * 6PCS