TopYart Cordless Rechargeable Bug Zapper Mosquito Insect Electric Fly Swatter Racket Diamond network of three layers network with light steel. round/flat plug mosquito swatter/fly swatter Integrated design, self-excited oscillation at high. frequency, 3 times the voltage amplification circuit. Large power grids, kill mosquito fast and efficiently. Energy conservation and environmental protection, healthy and safety. Three layers of metal mesh