5GB / 4GB configuration (likely referring to flash storage and RAM capacities).
Smart TV, specifically for repair or re-installation purposes. Technical Specifications
If you obtain the full set of .rar parts, follow these general steps for a USB recovery:
With the TV unplugged, insert the USB. Hold the Power button on the TV (not the remote) and plug the TV into the wall. Keep holding it until the software update screen appears or the standby light begins flashing rapidly.