This indicates the security bit or binary version of the device. You can only flash a file that is equal to or higher than your current binary level.
Never attempt to flash a U1 file on a U2 device; this can lead to a hard brick.
Ensure your phone is at least 30% charged and the correct Spreadtrum/UNISOC drivers are installed on your PC.
Flashing the A035F U2 PAC combination file is primarily done for the following technical reasons:
To use the file, you will need the SPD Flash Tool or specialized GSM boxes like Pandora Box or Z3X .
Do you need the specific for the U2 stock firmware to flash back after using the combination file?
Click the Play/Triangle icon in the tool to begin. Once finished, the device will boot into a basic factory test menu. Important Precautions
Samsung A035F imei Repair U1, U2, U3 | Without Root One Click Only