Most L210 models use the SPD chipset , requiring the SPD Upgrade Tool . If yours is a rare MTK variant, you will need the SP Flash Tool . Flashing via SD Card (Official Method) This is the safest manual method recommended by ZTE:
Click the icon in the tool interface. Power off your ZTE Blade L210 completely. Zte Blade L210 Firmware
Click on the located at the top-left corner of the interface. Most L210 models use the SPD chipset ,