Mobile phone signal jammer Keeps you away from noise or disturbance of unexpected cellular phone calls. It can paralyze cellular phone signals within an effective area. And all the specified frequency bands will be blocked simultaneously. It can be applied at meeting room, conference room, museum, gallery, theater, concert hall, church, temple, restaurant, classroom, training center, factory, bank, train, and bus, for some locations of special purpose such as hospital, and gas station. It is easy to install and operate the device. No adjustment is needed. If not well paralyze happened, please change the installation location or position or to check if any cellular control stations or repeaters installed just in nearby. 22.8*5.8*12cm 1.5kg