The theory Mini Ultrasonic Mosquito Repeller adopts high-tech,using ultrasonic principle to repel mosquito, make a pest uncomfortable enviroment drive pests away. Applicability Mini Ultrasonic Mosquito Repeller :Home and apartments,food service,Businesses,Farms and so on.They keep an area of up 30 square meter free from mosquitoes Features 1.Only effective with mosquito, does not interfere with the operation of radio,televison or other electronic equipment 2.Steady performance and fast returns.If you continue used 5-7 days will repel all mosquitoes indoor. 3. Cabinet and exquisite, cute appearance like our human eyes Method 1.Plug unit intosocket of 220V/110V AC wall outlet. 2.When the power is connected , the LED pilot lamp will light up indicating that your Ultrasonic Mosquito Repeller is working properly 3.When it is working ,very faint sound waves will be issued Specifictions 1.Power supply:AC 220-230V 2.Frequency range:50KHz 3.Consumption just 0.5 Watts. Attention The environment have long time nobody stay,please pull out the plugThat product is not waterproof,please do not used in damp environment.Do not closed your ear to the machine,so as to avoid hearing demage.