Warm Reminder: Please use the low frequency mode when you are in the room. Low frequency mode has no noise or a little noise but people can't hear it. Innovative Frequency Conversion Technology: This indoor tonic emits invisible electromagnetic waves to repel insects, rats, rats, mosquitos, ants, spiders, cockroaches and other insects. No need to kill them. Please note that our ultrasonic repellent will work within 2 to 4 weeks, depending on the number of infestation. Then we can say goodbye to vermin and rats. Plug and Play Full Coverage: The ultrasonic insect repeller can be used in bedrooms, bathrooms, garages, kitchens, offices, warehouses and other places. Safe and Environmentally Friendly: The bug repellent has no poisons, chemicals, traps and kills, 100% safe and harmless to humans, children and pets. It is a method of physically repelling pests. It is non-toxic, environmentally friendly, and absolutely safe for children and pets. It is an insect repellent that combines advanced technology and humanitarianism. But don't use it if you have hamsters as pets in your home.