1. Ultrasonic Mice Repeller is effective in controlling mice, rates, and most other Common pests. 2. Laboratory research has shown ultrasonic waves attack the auditory and nervous systems of most common pests causing them pain and discomfort.. 3. These high-intensity ultrasonic waves are out of the range of hearing of humans and most household pets such as dogs, cats, fish and birds, and farm animals, will not interfere with televisions, radios, electronic burglar alarms, fire or smoke detectors, pacemakers, hearing aids or other electronic equipment. Specification Material: ABS plastic Power supply: 220V AC power Power Consumption: 3-9 Watts Frequency: 22KHZ-25KHZ Effective area: 500sq.ft Unit size: 10x10x6.2CM Blister packaging size: 20.3x18.5x8.5cm Package: 20FT' : 16416PCS 40FT' : 34080PCS 40HQ: 39936PCS