As most cell phones want the faster modes of conversation such as 4G or 3G, downgrading to 2G can demand blocking frequency ranges for 4G and 3G.[19] Some IMSI catchers also can block assistance to help you no more use your cellphone for making or receive calls and textual content https://www.shoghicom.com/all-products/integrated-imsi-catcher--mobile-locator-system