What is a voice network card?

In other words, there are not only free voice calls, but also cards that give away traffic.

Flow card, also called mobile data card, is a SIM card that provides wireless Internet access for portable devices such as computers. In addition to wireless Internet access, SMS, telephone and other functions.

Flow cards can be used in places where there is no network interface, and desktop computers and notebook computers can use mobile data cards to access broadband services through operators' mobile data networks.

Flow card related extension: SIM card

SIM card is the key for GSM mobile phone to connect to GSM network. Once the SIM card is removed from the mobile phone, the mobile phone will not be able to enjoy all kinds of services provided by network operators except emergency calls. SIM card can not only be used as a key, but also provide a lot of convenience for users. Users only need to insert or embed the SIM card into any GSM terminal to realize communication.

SIM card also manages a lot of information provided to users, which can be used to store short messages, especially those received when users are away or absent.