Research found that: only pregnant mosquitoes will bite the mother. In the meantime, the mother mosquito mosquito will make every effort to avoid the public. In addition, the biosphere, there is a natural enemy of mosquitoes ---- dragonfly. According to this basic principle of biology, we designed a very special high-tech electronic inverter circuit, simulate the sound of public mosquito and dragonfly wings wings jitter jitter voice. Mosquito bites both heard the sound, it will immediately run away, so as to achieve the purpose to drive away mosquitoes.