What is the coverage of the NB module?

National coverage. The Ministry of Industry and Information Technology has issued a document: It is required that by 2020, NB-IoT network achieves universal coverage across the country, and achieves deep coverage for indoor, traffic road networks, low-level pipe networks and other application scenarios, with a scale of 1.5 million base stations. If the base station near your position does not support NB devices, you can contact the person in charge of the operator to apply for activation.