How A GSM SIM Card Works?
A GSM-enabled phone that can use SIM cards from several phone carriers and operates on the frequency of the destination countries must be unlocked in order to use a GSM SIM card. That frequency is 900 MHz or 1800 MHz in several European nations. It is crucial that a phone operates on the correct frequency since even if it can access the GSM network, it will not function if it is not. The GSM SIM card may be used after a user has an unlocked phone that is compatible with the GSM network and the right frequency. No matter what country the user is in, this card enables them to utilize the same phone number abroad.