Why mosquito afraid of Ultrasonic Pest Repeller?

 Ultrasonic Pest Repeller is a electronic Pest Repeller device which emits high pitched sound at a frequency which discomfort, kill or drive away the household pests. These Pest Repellers are more easy and convenient to use than any type of other Pest Repeller. These easily get pluged into electric outlets but some are battery operated to use them in Garden or any other places. When turned on the machine emits high pitched sound which were unconditional to human being but can irritate some sensitive human beings. 

Which type of Pest these Repeller work on?

1. Cockroaches
2. Mosquitoes
3. Bed bugs
4. Flies
5. Silverfish
6. Birds
7. Rats and mice