Cellphone Jammers, Mobile Phone Signal Booster, Prison Jammer manufacturer / supplier in China, offering 1-5m Jamming Range Signal Jammer for Phone WiFi and GPS with Built-in Battery, Pocket-Sized Signal Jammer with 8 Channels Jamming for 2g/3G/4G, Wi-Fi, Bluetooth and GPS, Portable Pk800 Signal Jammer for 2g/3G/4G, Wi-Fi, Bluetooth and so on.