NO CHEMICALS: The ultrasonic insect repeller includes 8 citronella oil pads that emit a safe, insect repelling aroma, without the use of any harmful chemicals to you or the surrounding environment PORTABLE SIZE: The compact size of the ultrasonic insect repellent makes it easy to use inside the home, in the yard, on campsites, hiking, etc ULTRASONIC TECHNOLOGY: This mosquito killer emits a safe and harmless ultrasonic sound, saving you and your guests from excess noise. The quiet sound waves will send all unwanted bugs and insects scurrying