Cellphone Jammers, Mobile Phone Signal Booster, Prison Jammer manufacturer / supplier in China, offering Multi-Frequency Mobile Phone Signal Blocker with 12 Antennas for Enhanced Privacy, 16 Watts Stationary 6 Bands Cellphone Signal Jammer Cover Radius up to 10-50 Meters, High Power Profressional 6 Band Cellphone Signal Jammer Model Cover Radius up to 50-150 Meters and so on.