Dear Customer, To know whether the GNext product you are buying is Genuine or not please enter SERVICE TAG/IMEI in the box given The service tag/IMEI number can be found on the base of your device or on the box. In this example the service tag number is FFKN22S and IMEI Number is 356979061650722 In case of iPhone, please use serial number if IMEI number is not validating. Service Tag/IMEI: