When register your mobile phone number, you will get a UIM card (User Identity Module) provided by the network operator. With this UIM card, which stores many parameters required for communications, you can use the various functions of the phone and save personal information, including PIN (Personal Identification Number), contact, SMS and other system services. Please use the UIM card carefully. Twisting or pressing it may cause damage. If it is lost, please contact your network operator immediately for help.