Keep in mind, that a mobile signal jammer will not only block voice and text on your phone, it also interferes with GPS, WiFi, and probably most problematic of all — police radar. That’s why, as mentioned above, the Federal Government has banned the sale, promotion, and use of cell phone signal jammers in the US. So if you were envisioning a little peace and quiet, courtesy of a shiny new signal blocker, you might just have to settle for earplugs. http://www.alasartech-security.com/signal-jammer/